There are two sentences (S1) and (S2) based on commonly used word(s), which are highlighted. Read the two sentences carefully and mark the response that denotes the correct use of these words in each of the two sentences.
(S1) I have not seen her since a long time.
(S2) It has been a while since I saw her.

Correct option is B

(S1) is incorrect because the preposition "since" is used improperly. "Since" should be used with a specific point in time, not a duration. The correct sentence would use "for" instead, as in "I have not seen her for a long time."
· (S2) is correctly structured, using "since" appropriately with a past simple tense to indicate a point in time after which something has not happened. It is an idiomatic and grammatically correct way to express that some time has passed since the last occurrence.
· Therefore, the correct answer is that (S1) is wrong due to incorrect preposition use, while (S2) is correctly structured.