The Use of the Words если and ли

Использование слов если и ли

The word ли is used to express a question or uncertainty.

When it occurs in a simple sentence, it is not translated into English:

Хороший ли он человек? - Is he a good man?

When it occurs in a complex sentence, it is rendered in English by whether or if:

Интересно, будет ли завтра дождь? - I wonder if it will rain tomorrow.

The English counterpart of the Russian word если is if.

Если introduces conditional clauses, which may either precede or follow the main clause.

Если ты будешь свободен, пойдём в театр. - If you are free, let's go to the theater.

 С удовольствием пойду, если буду свободен. - I'll go with pleasure if I'm free.