nguyên tắc chọn if hay whether

Nguyên tắc chọn IF hay WHETHER
* Thường thì cả Whether / If được dùng trong câu gián tiếp khi giới
thiệu câu hỏi dạng "yes/ no". Tuy nhiên, whether lại được cân nhắc là
"formal" hơn if.
VD:
Let me know whether you will be able to attend the conference.
The CEO will decide whether this is a risk worth taking.
VD:
He asked me whether I felt well.
We're not sure if they have decided.
* Sau đây là những trường hợp chọn WHETHER thay vì IF
- Động từ DISCUSS
VD:
We discussed whether he should be hired.
They discussed whether to invest in the new idea.
- Chỉ dùng Whether sau giới từ
VD:
We talked about whether we should go or not.
I looked into whether he should stay.
- Chỉ dùng Whether trước to V
VD: She can't decide whether to buy the house or wait.
He considered whether to give up the position or quit next year.
Bài tập: Chọn đáp án đúng:
1. Let's discuss ______ we should go or not.
A. whether
B. if
2. They were wondering ______ to come or not.
A. whether
B. if
3. (Formal) Let me know ______ you will be able to attend the
conference.

A. whether
B. if
4. (Informal) Tell me ______ you can come to the party or not.
A. if
B. when
5. We talked about ______ we should go or not.
A. whether
B. if
6. We're not sure ______ they have decided.
A. if
B. who
7. She's the one _____ telephoned last night.
A. if
B. who
8. I looked into ______ he should stay.
A. whether
B. if
9. (Formal) The CEO will decide _____ this is a risk worth taking.
A. whether
B. if
10. (Informal) He asked ______ I could help him with his math
homework.
A. whether
B. if