If / whether - When do to use these words?

[emogen]

Hi guys!

I would like to know when I use:
>> If;
>> Whether;

For example, in this sentence:
"Could you tell me whether you have a juice?"
Why I don't use "if" in this case?

I generally use "if". "Whether" is a new word for me...
Can you explain me when I use "Whether" and the difference between these two words?

Thanks again,

Emerson

 

[emsr2d2]

Hi guys!

I would like to know when I use:
>> If;
>> Whether;

For example, in this sentence:
"Could you tell me whether you have a juice?"
Why I don't use "if" in this case?

I generally use "if". "Whether" is a new word for me...
Can you explain to me when I use "Whether" and the difference between these two words?

Thanks again,

Emerson

Can you tell me if you have juice?
Can you tell me whether or not you have juice?

As you can see, "whether" is normally connected with "or not".

Because I'm in a pedantic mood, please be aware that if you start a question with "Can you tell me ..." there is a danger that the respondent will simply say "Yes, I can" or "No, I can't" without giving you the answer you were looking for.

Do you have juice?
Please tell me if you have juice.

 

[TheParser]

***** NOT A TEACHER *****


(1) I think that some very strict teachers and books say this:

(a) Use "whether" to introduce a noun clause:

(i) Could you tell me whether you have juice?

(a) A noun clause can usually be replaced by the word "something."

(i) Could you tell me something?

(ii) I want to know whether you speak French. (know something)
(iii) Did they tell you whether they were coming or not? (tell you something)

(b) Use "if" in adverbial clauses of condition:

(i) I will come if I have time.
If you do that again, you will be very sorry, dude!
I will take an umbrella if it rains.


(2) I think that many native speakers would feel comfortable using "if" in those

"whether" sentences that I gave you. But some people feel that it is better to

maintain the distinction between the two "conjunctions."