Today I post a grammar lesson on the difference between if and whether. These two words normally pose problems for English students, since the translation into Spanish is the same in both cases (si). Here I'll post an explanation on when to use each. Hope it helps!
In very general terms, we use if in conditional sentences and whether to show that two alternatives are possible. In the cases where both are possible, whether is understood as more formal.
That said, let us look at both conjunctions in some deeper detail:
If and whether are interchangeable in the following contexts:
- IN REPORTED OR INDIRECT YES/NO QUESTIONS:
She asked if / whether I'd be attending the party.
Do you know if / whether dinner will be ready soon?
I don't know if / whether she's coming or not.
- "WHETHER / IF ... OR ... " CONSTRUCTIONS
I'd really like to know whether / if he's lying or telling the truth.
Use ONLY whether in the following contexts:
- TO PRESENT TWO ALTERNATIVES:
Let the principal know whether you'll attend the meeting
(there are two alternatives: you'll attend the meeting or you won't. You have to inform the principal in either case).
Let the principal know if you'll attend the meeting
(this sentence is grammatically correct, but the meaning is different. In this example, the principal is only be told if you'll attend the meeting. Therefore, if you'll attend the meeting is a condition, it doesn't present two alternatives).
- AFTER PREPOSITIONS:
My final decision depends on whether you agree
I would like to talk to you about whether you'll continue working here
- BEFORE INFINITIVES:
I've been thinking whether to quit my job
(if to quit).
She can't make up her mind whether to marry him
(if to marry him).
- DIRECTLY BEFORE OR NOT:
(Note that or not can be placed at the end of the sentence. In that case, if is possible: Please, tell me if you agree or not).
- WHEN WHETHER STARTS A CLAUSE:
Whether she liked the present, I don't know.
Whether he comes or not is nor my concern.
I don't care whether you study or waste your time.
(If we use if in these contexts it would be understood as a condition)
- WHEN WHETHER EXPLAINS SOMETHING THAT COMES BEFORE:
You have to answer my question, whether I can count on you (that is my question).
Use ONLY if in the following contexts:
- TO INTRODUCE A CONDITION:
If I had the chance I would travel all around the world.If it hadn't been for my family, I wouldn't have got so far.
YOUR TURN! :)
Now check how much you can remember with the following exercises!