Having lost his key .A. he couldn’t enter the roomB. the gatekeeper offered to helpC. the

问题补充：

Having lost his key，.

A. he couldn’t enter the room

B. the gatekeeper offered to help

C. the door was forced open

D. the room couldn’t be entered

答案：

(答案→)A. he couldn’t enter the room

B. the gatekeeper offered to help

C. the door was forced open

D. the room couldn’t be entered

解析：考查句子结构：逗号前面是现在分词的完成式做状语，说明句子的主语应该是lost his keys的逻辑主语，应该是he，句意：丢了钥匙后，他不能进入房间。选A。