Common Mistakes in English - Whether / If

Whether and if can often be used interchangeably. However, there are some instances in which only one form can be used. Learn the rules of these two commonly interchanged words that sometimes cause a common mistake in English.

Whether / If

Both whether and if are used to introduce a yes/no question:


He asked me whether I felt well.
We're not sure if they have decided.

The verb discuss generally takes whether rather than if.


We discussed whether he should be hired.
They discussed whether to invest in the new idea.

After Prepositions

Use only whether after prepositions:


We talked about whether we should go or not.
I looked into whether he should stay.


Use only whether before infinitives:


She can't decide whether to buy the house or wait.
He considered whether to give up the position or quit next year.

Formal / Informal

Generally, whether is considered more formal than if.


Let me know whether you will be able to attend the conference.
The CEO will decide whether this is a risk worth taking.

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