Question

Fill in the blank with a suitable form of verb:
Water___________ (cover) most of the Earth's surface.
a. covers
b. has covered
c. is covering
d. had covered

Answer 1

Hint: Verb has five forms in English namely - the base form, the present tense form, the past tense form, the present participle, and the past participle.

Complete answer:
From the hint given to us, we know that verb has five forms in English namely - the base form, the present tense form, the past tense form, the present participle, and the past participle. Thus, we can infer from this that the suitable verb form will agree with the context of the given sentence.

a. Covers is the present tense form of the verb and is in simple present tense, cover. It agrees with the context of the given sentence which indicates generalisation. Hence, option A is possibly the correct answer.
b. Has covered is in the present perfect tense. Present perfect tense is used to indicate an activity that is already over. It does not agree with the context of the given sentence. Hence, option B is not the correct answer
c. Is covering uses the present participle form of the verb and is in present continuous tense. Present continuous is used to indicate an activity which is not yet over. It does not agree with the context of the given sentence. Hence, option C is not the correct answer
d. Had covered is the past perfect tense which is used to indicate past to past. It does not agree with the context of the given sentence. Hence, option D is not the correct answer.

Thus, we can conclude that option A is the correct answer.

Note: A verb has three main types of tenses - past, present and future. These are used with respect to the time of the activity.