Mr. Smith is always on time for everything. How it be that he was late for the flight?A.

问题补充：

Mr. Smith is always on time for everything. How it be that he was late for the flight?

A. can

B. must

C. may

D. need

答案：

(答案→)A. can

B. must

C. may

D. need

解析：考查情态动词辨析。本题是强调句型的一个变式：It 情态动词 be…that/who…其它成分；本句是其特殊疑问句的形式。是对具体的发生进行的强调。句意：斯密斯先生总是很准时，怎么可能会乘坐飞机迟到呢？can可能；must一定，必须；may也许；need需要；根据句意说明A正确。