Derek1988 wrote:Hello, I am an italian future test GMAT test maker and as every non-native english speaker, I have troubles with SC

One of mine major problems is the usage of wether and if. Time to time you can found some SC questions where the different usage between "wether" and "if" is needed to be known in order to solve the question: can someone explain me when "wether"/"if" is required and when it is not?

tnx a lot

Have a look here : https://www.grammar-monster.com/easily_c ... hether.htm

Hi there.

In brief, 'if' is used in various conditional sentences in the condition part of the sentence. Notice then that one part/clause shows a condition (the 'if' clause) and the other clause shows the result of the condition. For 'if' sentences your job is to learn the various types of conditionals (how these sentences are constructed, what verb tenses to use, and what the exceptions are).

Examples:
If I go, she will follow.
If I ate the cake, I would be happy.
I would have gone to the fair if I had heard about it on time.

'Whether' is used to show an option between two choices or deals with a yes/no option.

Examples:
I am not sure whether I want an apple or an orange. (choice between two possibilities)
He hasn't decided whether he will go (or not). (yes he will go or no he will not go)

Note that when dealing with the latter type (yes or no) it is considered redundant to include 'or not'; in other words do not include the 'or not') so that the correct form now looks likes this:

He hasn't decided whether he will go.



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