when you leave the room,make sure ____all the lights are turnde off.

题目

when you leave the room,make sure ____all the lights are turnde off.
a.if b when.c whether d that

答案

D
make sure表示“务必”,“确信”,“弄明白”,后面常接 of/about sth.或that引导的宾语从句.make sure后通常不接不定式.