Fourth grade knowledge of nature.

1. Little knowledge of science in grade four (I)

Simple and easy-to-learn scientific knowledge

The mystery of automatic rotation

Thinking: Why do cartons full of water rotate?

Materials: empty milk box, nails, 60 cm long rope, sink, water.

Operation:

1. Punch five holes in the empty milk box with nails.

2. One hole is in the middle of the top of the carton, and the other four holes are in the lower left corner of the four sides of the carton.

3. Tie a rope about 60 cm long on the top hole.

4, put the carton on the plate, open the carton mouth, quickly fill the carton with water.

5. Lift the rope at the top of the carton by hand, and the carton rotates clockwise.

Description: the water flow produces equal and opposite forces, and all four corners of the carton are pushed by this force. As this force acts on the lower left corner of each side, the carton rotates clockwise.

Create:

1. If a hole is punched in the center of each side, how will the carton rotate?

2. If the hole is located in the lower right corner of each side, which direction will the carton rotate?

Boat and paddle

Thinking: Have you ever seen boating? Rowing by yourself? Do you know why the ship is moving on the water?

Materials: scissors 1, cardboard 1, rubber band 1, washbasin and water 1 basin.

Process:

1. Cut the cardboard into about 12cm * 8cm long.

2. One end of the bow is cut into a sharp shape, and the other end is cut out of the center of the stern by about 5 cm.

3. Cut a piece of cardboard about 3cm * 5cm to make ship pulp.

4. Tie a rubber band at the stern and tie an oar.

5. Turn the cardboard paddle counterclockwise and tighten the rubber band, and the boat will move forward.

6. If the cardboard paddle is rotated clockwise to tighten the rubber band, the boat will move backwards.

Description:

1, the rubber band twists in different directions, but the ship's direction is just the opposite.

2. The power of paper boat movement comes from the energy of rubber band torsion.

2. Take care of the little knowledge and 20 science subjects in the second volume of the fourth grade.

Science, which means learning by subject, later refers to gradually forming a complete knowledge system through careful classification (such as mathematics, physics, chemistry, etc.). ). It is the knowledge about the practice of discovery, invention and creation, and it is the general name of the knowledge system for human beings to explore, study and understand the changing laws of everything in the universe.

Science is an orderly knowledge system based on testable explanation and prediction of the form and organization of objective things. In an ancient and closely related sense, "science" also refers to the discipline itself that can reasonably explain and reliably apply knowledge. Professional practitioners of science are customarily called scientists. [ 1-4]

Since classical times, science has been closely linked as a kind of knowledge. Scientific methods laid the foundation, emphasizing the reproducibility of experimental data and its results. In the early modern western world, "science" and "natural philosophy" can sometimes be used interchangeably. In the western world, until the17th century, natural philosophy (natural science) was regarded as an independent branch of philosophy, with the same origin as materialism. [5-6]

In modern usage, "science" often refers to the pursuit of knowledge, which is not only a way of knowledge itself, but also often limited by the study of these branches that seek to explain the material world. In the17th century and18th century, scientists increasingly sought to formulate knowledge about natural laws, such as Newton's laws of motion. In the course of the19th century, the word "science" has been increasingly associated with the scientific method itself, in order to study the disciplinary methods in the natural world, including physics, chemistry, geology and biology. It was in the19th century that the word scientist was distinguished by naturalists as knowledge of nature and knowledge creation. [7]

However, "science" continues to use a subject that represents reliable and teachable knowledge in a broad sense, which is reflected in modern terms, such as library science and computer science. This is also reflected in the names of some academic research fields, such as "social science" or "political science".

3. Little knowledge of the fourth grade of mathematics

The knowledge points of mathematics in the fourth grade of primary school are summarized in the first volume of the fourth grade. The knowledge points are summarized in 1. Understanding of large numbers: understanding of numbers within (1) billion:100000:10/0000; One million:100000; Ten million:100000; 1 100 million:1010 million; 2. Digital scale: Digital scale is a reading method for people to remember and read * * * numbers. On the basis of numerical system (numerical order), read and write numbers according to the principle of three-digit or four-digit grading.

Usually, in the writing of * * * numbers, decimal points or spaces are used as the marks of each number level, and the numbers are separated from right to left. 3. Grade classification (1) The four-digit classification method is a classification method with four digits as a grade.

The habit of reading in our country is like this. Such as: ten thousand (four zeros after counting), one hundred million (eight zeros after counting), and one trillion (12 zeros after counting, which is a normal number).

These levels are called Level 1, Level 10,000 and Level 100 million respectively. (2) Three-digit classification is a classification with three digits as an order of magnitude.

This western classification, this classification is also an internationally accepted classification. For example, thousands, followed by three zeros and millions, six zeros and one billion, and nine zeros.

4. Numbers: Numbers refer to writing numbers in a row side by side, and each number occupies a position. These positions are called numbers. Starting from the right end, the first place is the unit, the second place is the tenth place, the third place is the hundred places, the fourth place is the thousand places, and the fifth place is the ten thousand places, and so on.

This shows that the concept of counting unit and number is different. 5. Generation of Numbers: Origin of * * * Numbers: After ancient Indians created * * * numbers, they spread to * * * regions around the 7th century.

By the 3rd century A.D./KLOC-0, the Italian mathematician Fibonacci wrote Abacus, in which he introduced the number of * * * in detail. Later, these figures spread from * * * to Europe. Europeans only know that these numbers are imported from * * * regions, so they are called * * * numbers.

Later, these figures spread from Europe to all countries in the world. * * * Numbers were introduced into China from about 13 to 14 century.

Because there was a number called "Chip" in ancient China, which was convenient for writing, the number * * * was not popularized and used in time in China at that time. At the beginning of this century, with the absorption and introduction of foreign mathematical achievements in China, the number * * * began to be used slowly in China, and it has only been popularized and used in China for more than 100 years.

* * * Numbers have now become the most commonly used numbers in people's study, life and communication. 6. Natural number: a number used to measure the number of things or to indicate the order of things.

That is, the numbers represented by the numbers 0, 1, 2, 3, 4, and ... the numbers representing the number of objects are called natural numbers, and they form an infinite group one by one from 0 (inclusive).

7. Computing tools: abacus, calculator and computer. 8. Ray: In geometry, the figure formed by a point on a straight line and its edge is called a ray.

As shown in the following figure: 8. Ray characteristics (1) A ray has only one endpoint, and it extends from one endpoint to the other indefinitely. (2) Ray is unpredictable.

9. Straight line: A straight line is the trajectory of a point moving in the same or opposite direction in space. 10. Line segment: A line segment is represented by letters or lowercase letters representing its two endpoints. Sometimes these letters also represent the length of the line segment, which is recorded as line segment AB or line segment BA and line segment A. ..

Where AB represents any two points on a straight line. 1 1. The line segment feature (1) has a finite length and can measure (2) two endpoints 12. Line segment attribute: (1) The line segment between two points is the shortest.

(2) The length of the line segment connecting two points is called the distance between these two points. (3) Two points on a straight line and the part between them are called line segments, and these two points are called the endpoints of the line segments.

There is no distance in a straight line. Ray has no distance.

Because a straight line has no end point, and a ray has only one end point, it can extend indefinitely. 13. The static definition of an angle (1) is called an angle.

This common endpoint is called the vertex of the angle, and these two rays are called the two sides of the angle. (2) Dynamic definition of angle The graph formed by the rotation of light from one position to another around its endpoint is called angle.

The endpoint of the rotated ray is called the vertex of the angle, the ray at the starting position is called the starting edge of the angle, and the ray at the ending position is called the ending edge of the angle 14. Symbol of angle: ∠ 15. Type of angle: the size of the angle has nothing to do with the length of the side; The size of an angle depends on the degree to which both sides of the angle are open. The bigger the opening, the bigger the angle. Conversely, the smaller the opening, the smaller the angle. In dynamic definition, it depends on the direction and angle of rotation.

Angles can be divided into acute angle, right angle, obtuse angle, right angle, rounded corner, negative angle, positive angle, upper angle, lower angle and 0 angle, which are 10 respectively. An angle measuring system in degrees, minutes and seconds is called an angle system.

In addition, there are secret system, arc system and so on. (1) acute angle: an angle greater than 0 and less than 90 is called an acute angle.

(2) Right angle: An angle equal to 90 is called a right angle. (3) Oblique angle: An angle greater than 90 and less than180 is called obtuse angle.

16. multiplication: multiplication refers to how many times a number or quantity has increased. For example, 4 times 5, that is, 4 increases 5 times, or it can be said that 5 4' s are added together.

17. Names of numbers in the multiplication formula: "*" is a multiplication sign, numbers before and after the multiplication sign are called factors, "=" is an equal sign, and numbers after the equal sign are called products. 10 (factor) * (multiplication sign) 200 (factor) = (equal sign) 2000 (product) 18. Parallelism: Two straight lines on a plane, two planes in space or a straight line in space are said to be parallel when there is no common point between them.

As shown in the figure, the straight line AB is parallel to the straight line CD and marked as AB∑CD. Parallel lines will never intersect.

19. Vertical: two straight lines, two planes intersect, or a straight line intersects a plane. If the intersecting angles are right angles, they are called perpendicular to each other. 20. Parallelogram: A parallelogram with two groups of opposite sides on the same plane is called a parallelogram.

2 1. Trapezoid: Trapezoid refers to a set of quadrilaterals whose opposite sides are parallel and the other set of opposite sides are not parallel. Two parallel sides are called the bottom of the trapezoid, in which the long side is called the bottom and the short side is called the bottom; You can also simply think that the upper part is called the upper bottom and the lower part is called the lower bottom.

Non-parallel edges are called waist; The vertical section sandwiched between the two base sides is called the height of the trapezoid. 22. Division: Division rule: How many digits is the divisor, first.

4. What are the scientific knowledge of the fourth grade?

The first is the "weather" unit.

1. We can describe the weather by weather characteristics such as cloud cover, rainfall, temperature, wind direction and wind speed.

2. A table that records various weather phenomena every day is called a weather calendar.

3. The function of weather calendar: record and analyze meteorological information, summarize the previous meteorological laws and predict future weather changes.

4. In the weather calendar, the simplified wind speed grades are used to divide the wind speed: 0 is no wind, 1 is a breeze, and 2 is a strong wind.

5. When using a thermometer, it is necessary to wait until the liquid column in the thermometer stops rising or falling before reading.

6. Temperature has a great influence on the weather and is an important record data in the weather calendar. By observing and measuring the temperature of the atmosphere around us, we can know the local temperature. Temperature refers to the outdoor temperature in a cool and ventilated place. The outdoor temperature in a cool and ventilated place can better reflect the local temperature.

7. The law of temperature change in a day is that it rises first and then falls, with the lowest temperature in the morning and evening and the highest temperature at 2 pm.

8. Wind direction refers to the direction in which the wind blows. For example, the north wind blows from north to south. The wind direction can be measured by the wind vane. The direction pointed by the wind vane arrow is the wind direction. If the arrow points to the south, it is the south wind. Wind direction can be described in eight directions: east, south, west, north, southeast, northeast,

Southwest, northwest.

9. Wind speed is calculated by the number of meters per second. An anemometer is an instrument for measuring wind speed. Meteorologists abbreviate wind power as 13. Wind direction and wind speed are also important data in weather observation.

10. Precipitation is the basic feature of weather and also the important data in the weather calendar. Common forms of precipitation are: rain, snow, hail, fog, frost and so on. A rain gauge is a device for measuring rainfall. The unit of precipitation is millimeters. A straight container can be used as a rain gauge. (Remember a book: 13 page precipitation grade table)

1 1. In Qian Qian, the clouds floating in the sky are actually composed of thousands of water droplets or ice crystals, and their shapes are different.

12. According to the amount of clouds, it can be divided into sunny days, cloudy days and cloudy days. (Pictures will be used in this book P 14 to show the cloud cover in various weather.)

13. Meteorologists divide clouds into three categories: cumulus, stratus and cirrus.

5. There is more knowledge in the fourth grade of Chinese, which is urgent.

First, the fire prevention class 1, basic requirements: primary school students are not allowed to play with fire.

First, don't bring kindling such as matches or lighters; Second, it is not allowed to ignite at will, and it is forbidden to use fire for flammable and explosive materials; Third, it is not allowed to set off firecrackers in public places and throw lit firecrackers around. At the scene of the fire, primary school students and other minors should adhere to the principle of escaping first.

2, the way to deal with the fire, there is a fire at home, don't panic, take corresponding measures in time according to the fire: if the oil pan catches fire when cooking, quickly cover the lid tightly, so that the oil fire in the pan is extinguished due to lack of oxygen, and it cannot be put out with water. When a fire breaks out indoors, doors and windows cannot be easily opened to avoid air convection and form a large-scale fire.

When paper, wood and cloth catch fire, water can be used to put out the fire. When electrical appliances, gasoline, alcohol and cooking oil catch fire, earth, sand and mud and dry powder fire extinguishers can be used to put out the fire. If the fire is very big, you must report the fire immediately.

When you are trapped by fire, you should take different methods to escape according to different situations. If you lean down, cover your nose with a damp cloth.

3. How to call the police in case of fire? If a fire is found, the most important thing is to call the police, so as to put out the fire in time, control the fire and reduce the losses caused by the fire. The telephone number of the fire alarm is 1 19.

This figure should be kept in mind. In any part of the country, the telephone number for reporting fire to the public security fire department is the same. According to this figure, 1 1.9 is designated as the fire safety day every year.

You can't call the fire alarm at will. It is illegal to lie about the fire alarm, which disturbs public order. When there is no telephone, you should shout loudly or take other measures to attract the attention of neighbors and pedestrians, and assist in fire fighting or alarm.

4. How to get out of danger correctly in case of fire? In case of fire, correct and effective methods should be taken to save yourself and escape, so as to reduce personal injury and loss: 1) Once threatened by fire, don't panic, calmly determine your position, judge the fire according to the analysis of surrounding smoke, light and temperature, and don't take actions blindly. 2) In the bungalow, if the fire around the door is not big, you should leave the fire quickly.

On the other hand, you must choose another exit to escape (such as jumping out of the window) or take protective measures (such as soaking clothes with water, wrapping your head and upper body with warm quilts, etc.). ) before leaving the fire. 3) If you find a fire in a building, don't blindly open the doors and windows, otherwise it may lead to a fire.

4) If you are in a building, don't run around blindly, let alone jump off a building to escape, which will cause undue casualties. You can hide in the room or on the balcony.

Close the doors and windows, cut off the fire road and wait for rescue. Conditional, can continue to water the doors and windows to cool down, in order to delay the spread of the fire.

5) In a burning building, don't use the elevator to escape, but take the stairs through the fire escape. Because the elevator shaft often becomes a channel for setting off fireworks after a fire.

And the elevator may break down at any time. 6) If the fire is too fierce and you need to jump off a building to escape, you can jump off the second floor, but you should choose a soft ground. At the same time, throw the bedding upstairs to increase the cushion of the ground, and then slide down the window, so as to minimize the falling height and let the feet land first.

7) If you are sure, you can tie one end of the rope (or tear the sheets together) to the window frame and then slide down the ground along the rope. 8) When running away.

Try to take protective measures, such as covering your nose and mouth with a wet towel and wrapping your body with wet clothes. Second, traffic safety class China's "Traffic Law" stipulates that motor vehicles driving on roads in China must abide by the principle of driving on the right, and motor vehicle drivers and front seat passengers must wear seat belts.

1. How to pay attention to traffic safety when walking? When students go to school, it is the most crowded time of the day. There are many people and cars, so we must pay great attention to traffic safety. 1) Walk on the road and walk on the sidewalk; If there is no sidewalk, you should walk on the side of the road.

2) When going out in groups, it is best to walk in an organized and orderly manner; When going out together, don't chase, fight and play with each other; Pay attention to your surroundings when you walk. Don't look around, read newspapers or do other things while you walk. 3) Learn to avoid motor vehicles and don't argue with them on the road where there is no traffic police command.

4) Pupils should wear yellow hats when queuing after school, and it is best to wear colorful clothes in foggy and rainy days, so that motorists can find the target as soon as possible and take safety measures in advance. 2. What should I pay attention to when crossing the road? When crossing the road, the possible risk factors will increase greatly, so pay special attention to safety.

1) When crossing the road, obey the command of the traffic police; It is necessary to obey the traffic rules and achieve "green light, red light stops". 2) When crossing the road, take the crosswalk line; In sections with overpasses and underpasses, you should consciously take overpasses and underpasses.

3) When crossing the road, go straight and don't detour; In the section where there is no crosswalk, you should look at the left first, then at the right, and you can only cross the road when you confirm that there is no motor vehicle. 4) Don't climb over the safety fence and isolation pier in the middle of the road, and don't skate on the road.

5) Don't cross the street suddenly, especially if an acquaintance or friend is on the phone across the street, or if the bus you want to take has pulled into the station, and don't act rashly to avoid accidents. 3. How to identify traffic lights? There are two kinds of traffic lights. One is the red, yellow and green traffic lights used to direct vehicles, which are set in conspicuous places at intersections and are called vehicle traffic lights. The other is the red and green signal lights used to guide pedestrians to cross the road, which are set at both ends of the crosswalk and called crosswalk lights.

China's traffic laws and regulations also stipulate that when the traffic signal light: 1) is green, vehicles and pedestrians are allowed to pass, but turning vehicles shall not hinder the passage of straight vehicles and pedestrians. 2) When the yellow light is on, vehicles and pedestrians are prohibited from passing, but vehicles that have crossed the stop line and pedestrians that have entered the crosswalk can continue to pass.

3) When the red light is on, vehicles and pedestrians are not allowed to pass. 4) When the green arrow light is on, vehicles are allowed to pass in the direction indicated by the arrow.

5) When the yellow light flashes, vehicles and pedestrians can pass under the principle of ensuring safety. 4. Bicycle riding safety knowledge China is called "the kingdom of bicycles" and has the largest number of bicycles in the world.

But the bicycle is simple in structure, easy to fall and stable.

6. Syllabus of the Sound of Nature for Grade Four

There is no shortage of beauty in life. What is missing is the eyes that find beauty. In the vast sea of books, nature is a silent teacher. Next, I will talk about the inspiration I got from ants.

Once I found a nest of ants in the grass in the community. I saw them in groups of three or five, carrying food such as rice grains and biscuit residue. Some older ones actually moved a wasp, but the wasp was too big and the hole was too small. What shall we do? I hurried to find a magnifying glass to see how it transported such a big food into the hole.

I saw it cut the food into the same size as the hole with small thorns on its legs, and then moved the divided food into the hole one by one. I carefully observed the ant's legs. It turns out that ants have many small thorns on their legs, which are very sharp, just like cutting food with a Swiss army knife.

Suddenly, I had a wonderful idea. If you have tools like ants, you can cut materials very easily, and you can calculate the area and volume of objects. How much time and energy engineers will save in building houses and repairing roads! It looks like a metal bar. Open the lid, you can see the low-pressure water knife with a diameter of about 5 cm, which is very safe to use. The other end is a searchlight, which is connected with a microcomputer. It can simulate the appearance of an object, calculate how much material is needed, how much will be lost, and what it will look like after completion. It is widely used in architecture, sculpture and cutting-edge technology, such as drilling and grinding. Although all this is just a mirage, I will develop it one day.

Students, let's go out of the room together and listen to the sounds of nature. Follow the footsteps of nature and you will find something.

7. What are the first to third natural stages of tide watching in the first volume of the fourth grade?

Watching the tide-the full text of the text "Watching the tide" has been called the wonder of the world since ancient times.

The full text of Watching Tide describes the spectacular scene of watching Tide in Qiantang River on August 18th of the lunar calendar. The content of the tide-watching essay is selected from Zhao Zongcheng and Zhu Mingyuan's recent Happy Meeting Qiantang Life.

The first volume of the fourth grade of primary school Chinese, People's Education Edition "Watching the Tide of Qiantang River", has been called the wonder of the world since ancient times. August 18th of the lunar calendar is the annual tide-watching day.

This morning, we came to Yan Guan Town in Haining, which is said to be the best place to watch the tide. We followed the tide watchers to the seawall levee.

The vast Qiantang River unfolds in front of us. The river is calm and wider to the east, and it is covered with a layer of misty mist under the sunshine after the rain.

Zhenhai Ancient Pagoda, Zhongshan Pavilion and Tide Observatory stand by the river. In the distance, several hills are looming in the clouds.

Before the tide came, the seawall levee was already crowded with people. Everyone looked east with their heads held high, waiting and expecting.

At about one o'clock in the afternoon, there was a rumble in the distance, like a muffled thunder rolling. Suddenly, people are buzzing and we are told that the tide is coming! We stood on tiptoe and looked eastward, but the river remained calm and unchanged.

After a while, the noise became louder and louder. I saw a white line at the junction of water and sky in the east, and the crowd was boiling again. The white line quickly moved towards us, gradually elongated and thickened, and crossed the river.

Approached, I saw white waves rolling, forming a water wall more than two meters long. The tide is getting closer and closer, like thousands of white horses going hand in hand, galloping mightily; The sound is like a landslide, as if the earth were shaken by an earthquake.

In an instant, the tide rushed to the west, but the aftermath was still rolling all over the sky, and the wind was still whistling on the river. It was a long time before the Qiantang River calmed down.

Looking under the embankment, the river has risen by two zhangs. Note: The text of Watching the Tide is selected from Zhao Zongcheng and Zhu Mingyuan's recent Welcome to qiantang bore.

The autumn tide in Qiantang River is more spectacular than other places, which is related to the special local topography. The place where Qiantang River enters the sea is called Hangzhou Bay.

Hangzhou Bay is trumpet-shaped, with a width of100km in the east and only 3km in the west from Yan Guan Town, Haining City. At high tide, the tidal bore comes from the mouth of the bay and rushes to the west. Constrained by the narrowing banks on both sides of the strait, the water surface is getting narrower and narrower, the tidal bore is advancing, and the resistance is getting higher and higher, forming a surging spectacle.

Explanation of key words in Qiantang River tide-watching article: the wonders of the world-a rare magnificent landscape lying across the world-the meaning of lying across it-standing on it like a cage cover-looming like a mountain peak-describing a vague sea of people-describing how many people get together-connecting water and sky-referring to the sound when a strong earthquake occurs, this lesson will describe the tide. Other words: hold your head high, look at the East, people are buzzing (antonym: silence), calm (antonym: wind whistling, stormy waves), white waves are rolling across the river hand in hand, surging and rolling all over the sky (synonym: overwhelming), and the wind whistling is shivering. Please give a good comment, thank you.

8. Who knows the little knowledge of fourth grade mathematics?

First, the fire prevention class 1, basic requirements: primary school students are not allowed to play with fire.

First, don't bring kindling such as matches or lighters; Second, it is not allowed to ignite at will, and it is forbidden to use fire for flammable and explosive materials; Third, it is not allowed to set off firecrackers in public places and throw lit firecrackers around. At the scene of the fire, primary school students and other minors should adhere to the principle of escaping first.

2, the way to deal with the fire, there is a fire at home, don't panic, and take corresponding measures in time according to the fire: if the oil pan catches fire when cooking, quickly cover the lid tightly, so that the oil fire in the pan is extinguished due to lack of oxygen, and it cannot be put out with water. When a fire breaks out indoors, doors and windows cannot be easily opened to avoid air convection and form a large-scale fire.

When paper, wood and cloth catch fire, water can be used to put out the fire. When electrical appliances, gasoline, alcohol and cooking oil catch fire, earth, sand and mud and dry powder fire extinguishers can be used to put out the fire. If the fire is very big, you must report the fire immediately.

When you are trapped by fire, you should take different methods to escape according to different situations. If you lean down, cover your nose with a damp cloth.

3. How to call the police in case of fire? If a fire is found, the most important thing is to call the police, so as to put out the fire in time, control the fire and reduce the losses caused by the fire. The telephone number of the fire alarm is 1 19.

This figure should be kept in mind. In any part of the country, the telephone number for reporting fire to the public security fire department is the same. According to this figure, 1 1.9 is designated as the fire safety day every year.

You can't call the fire alarm at will. It is illegal to lie about the fire alarm, which disturbs public order. When there is no telephone, you should shout loudly or take other measures to attract the attention of neighbors and pedestrians, and assist in fire fighting or alarm.

4. How to get out of danger correctly in case of fire? In case of fire, correct and effective methods should be taken to save yourself and escape, so as to reduce personal injury and loss: 1) Once threatened by fire, don't panic, calmly determine your position, judge the fire according to the analysis of surrounding smoke, light and temperature, and don't take actions blindly. 2) In the bungalow, if the fire around the door is not big, you should leave the fire quickly.

On the other hand, you must choose another exit to escape (such as jumping out of the window) or take protective measures (such as soaking clothes with water, wrapping your head and upper body with warm quilts, etc.). ) before leaving the fire. 3) If you find a fire in a building, don't blindly open the doors and windows, otherwise it may lead to a fire.

4) If you are in a building, don't run around blindly, let alone jump off a building to escape, which will cause undue casualties. You can hide in the room or on the balcony.

Close the doors and windows, cut off the fire road and wait for rescue. Conditional, can continue to water the doors and windows to cool down, in order to delay the spread of the fire.

5) In a burning building, don't use the elevator to escape, but take the stairs through the fire escape. Because the elevator shaft often becomes a channel for setting off fireworks after a fire.

And the elevator may break down at any time. 6) If the fire is too fierce and you need to jump off a building to escape, you can jump off the second floor, but you should choose a soft ground. At the same time, throw the bedding upstairs to increase the cushion of the ground, and then slide down the window, so as to minimize the falling height and let the feet land first.

7) If you are sure, you can tie one end of the rope (or tear the sheets together) to the window frame and then slide down the ground along the rope. 8) When running away.

Try to take protective measures, such as covering your nose and mouth with a wet towel and wrapping your body with wet clothes. Second, traffic safety class China's "Traffic Law" stipulates that motor vehicles driving on roads in China must abide by the principle of driving on the right, and motor vehicle drivers and front seat passengers must wear seat belts.

1. How to pay attention to traffic safety when walking? When students go to school, it is the most crowded time of the day. There are many people and cars, so we must pay great attention to traffic safety. 1) Walk on the road and walk on the sidewalk; If there is no sidewalk, you should walk on the side of the road.

2) When going out in groups, it is best to walk in an organized and orderly manner; When going out together, don't chase, fight and play with each other; Pay attention to your surroundings when you walk. Don't look around, read newspapers or do other things while you walk. 3) Learn to avoid motor vehicles and don't argue with them on the road where there is no traffic police command.

4) Pupils should wear yellow hats when queuing after school, and it is best to wear colorful clothes in foggy and rainy days, so that motorists can find the target as soon as possible and take safety measures in advance. 2. What should I pay attention to when crossing the road? When crossing the road, the possible risk factors will increase greatly, so pay special attention to safety.

1) When crossing the road, obey the command of the traffic police; It is necessary to obey the traffic rules and achieve "green light, red light stops". 2) When crossing the road, take the crosswalk line; In sections with overpasses and underpasses, you should consciously take overpasses and underpasses.

3) When crossing the road, go straight and don't detour; In the section where there is no crosswalk, you should look at the left first, then at the right, and you can only cross the road when you confirm that there is no motor vehicle. 4) Don't climb over the safety fence and isolation pier in the middle of the road, and don't skate on the road.

5) Don't cross the street suddenly, especially if an acquaintance or friend is on the phone across the street, or if the bus you want to take has pulled into the station, and don't act rashly to avoid accidents. 3. How to identify traffic lights? There are two kinds of traffic lights. One is the red, yellow and green traffic lights used to direct vehicles, which are set in conspicuous places at intersections and are called vehicle traffic lights. The other is the red and green signal lights used to guide pedestrians to cross the road, which are set at both ends of the crosswalk and called crosswalk lights.

China's traffic laws and regulations also stipulate that when the traffic signal light: 1) is green, vehicles and pedestrians are allowed to pass, but turning vehicles shall not hinder the passage of straight vehicles and pedestrians. 2) When the yellow light is on, vehicles and pedestrians are prohibited from passing, but vehicles that have crossed the stop line and pedestrians that have entered the crosswalk can continue to pass.

3) When the red light is on, vehicles and pedestrians are not allowed to pass. 4) When the green arrow light is on, vehicles are allowed to pass in the direction indicated by the arrow.

5) When the yellow light flashes, vehicles and pedestrians can pass under the principle of ensuring safety. 4. Bicycle riding safety knowledge China is called "the kingdom of bicycles" and has the largest number of bicycles in the world.

However, the bicycle has a simple structure, falls down when touched, and has poor stability.