Question

The light in his room is off．He ________ to sleep．

[　　]

A．

may have gone

B．

can have gone

C．

could have gone

D．

must have gone

Answer 1

答案：D
解析：

表示肯定的推测要用must have done sth．，只用于肯定句中；may have done意为“有可能做了某事”；can have done表示推测时，只用于疑问句和否定句中；could have done意为“有能力做某事却没做”。