Question

【题目】Theconstructionofthelaboratory_________bytheendofJuly.

A. mustbecompleting

B. mustcomplete

C. musthavecompleted

D. musthavebeencompleted

Answer 1

【答案】D

【解析】考查情态动词表示推测。句意：实验室一定在上个月月底前就已经造好了。must have done表示对过去事情有把握的肯定推测。时态由“by”推出,，又因为主语是物，用被动。故答案为D。