Hello,
bansalgaurav, and welcome to the GMAT Club community. I agree with others that idioms appear to play a less prominent role in SC questions than they used to. A look through some pre-2000 official questions reveals as much. I doubt, for instance, that you would see a question on the modern exam that resembled
this one, in which the sole decision point rests on how to conjugate the verb
to be, or
this question, in which the key decision point is
regard as versus
regard to. Modern questions often test multiple splits, among which an idiom might pop up. For example, you should know how to use the idiomatic construct
not only X... but also Y (
here is a hard question that incorporates this idiom), as well as when to use
or or
nor in a sentence that involves negation. You should develop a habit of examining the full sentence for clues that may help you with meaning, parallelism, and so on. You do not have to know
everything to do well on SC, but you should have a solid foundational knowledge of grammar, punctuation, and, yes, even (more common) idioms.
Good luck with your studies.
- Andrew