How to use the weather and if?

The difference and connection between "whether" and "if"

First of all, it is very important that you write "weather" as "weather".

1. When if or what leads an object clause, we usually say "whether" after the verbs ask, see, say, know and out. Generally speaking, they are often used interchangeably, and if is often used in spoken English.

Two, if or guide the object clause, we should pay attention to three aspects, namely conjunctions, word order and tenses.

1, if or what cannot be used with that or when conjunctions (adverbs) and cannot be omitted.

2. If or not the object clause is leading, although it is doubtful, the word order of the clause should be declarative.

3. The object clause guided by 3.if or when should be consistent with the tense of the main clause, that is, the main clause is the simple present tense and the clause is in any tense; The main clause is the simple past tense and the subordinate clause is any tense in the past tense.

Third, the difference between if and what:

1. You can only use whether before infinitive.

2. Where is the fixed collocation ... or not, if ... or not.

After the preposition, you can only use what.

Whether the object clause is placed at the beginning of the sentence indicates emphasis, and only what can be used.

5, if it will cause ambiguity, only when. For example:

Can you tell me if you know the answer?

This sentence has two meanings: "Can you tell me the answer?" Or "If you know the answer, please tell me, ok?" If you use no, you can avoid ambiguity.

I hope the above answers can help you.