Study Skills | MCQs

Explanation

"Did not stop" is the correct past tense form of the verb "stop".

"Covered" is the simple past form that matches the sequence of past events.

This sentence follows the structure of two completed actions in the past.

Correct sentence:

"Ali did not stop studying until he covered all the exam topics."

Explanation

Explanation

A preposition is a word or group of words used before a noun, pronoun, or noun phrase to show direction, time, place, location, spatial relationships, or to introduce an object. Some examples of prepositions are words like "in," "at," "on," "of," and "to." Prepositions in English are highly idiomatic.