Question

– Who didn’t turn off the light after school yesterday?
– It ______ be Lucy. She told me she was the last one to leave the classroom.

A．must

B．mustn't

C．might

D．can't

Answer 1

A

试题分析：must必须，一定；mustn't禁止，千万不要；might 可能；can't不能。句意：昨天放学后谁没有关灯？根据下文，她告诉我她是最后一个离开教室的。可知前文指的是，一定是露西。故选A。