Used of time, distance, temperature, weather, etc. For example.

Distance: It's about 50 kilometers from here to my ranch.

It's about fifty kilometers from here to my ranch.

Time: It's still early.

It's still early.

Temperature: very hot.

It's really hot. Weather: If it rains (windy/snowy).

1. (refers to people or things mentioned or thought of) This, that, it.

This is our new car. I bought it yesterday.

This is our new car. I bought it yesterday.

(refers to inanimate objects, animals and plants, children of unknown sex, etc. ) it

What a beautiful baby-is it a boy?

What a beautiful child-is it a boy?

As the subject of impersonal verbs, it indicates time, climate, distance, etc. )

It's about 50 kilometers from here to my ranch.

It's about fifty kilometers from here to my ranch.

It is still early.

It's still early.

The weather is very hot.

It's really hot.

4. (placed at the beginning of a sentence or in a sentence to guide the following phrases or clauses)

I think it is worthwhile to go.

I think it's worth a visit.

5. (as a formal subject or object, used in sentence patterns that express emphasis)

But what I say here is the most important thing.

But I mean what I say here.

6. (Used after some verbs and prepositions, the meaning is vague, forming idioms)

Don't boss around your friends.

Don't put on airs in front of your friends.

Noun, noun