When his mother came in, Charlie pretended .
A. sleep
B. sleeping
C. to sleeping
D. to be sleeping
网友回答
A. sleep
B. sleeping
C. to sleeping
(答案→)D. to be sleeping
解析：这题考查pretend的搭配问题，pretend后面接不定式的各种形式，pretend to do“假装要做”，pretend to be doing“假装真正做”，pretend to have done“假装已经做了”，句意是：当妈妈回来，查理假装正在睡觉。选D。