Whoever leaves the lab last all the lights are turned off.A. make sureB. make sure ofC.

问题补充：

Whoever leaves the lab last, all the lights are turned off.

A. make sure

B. make sure of

C. be sure

D. be sure of

答案：

(答案→)A. make sure

B. make sure of

C. be sure

D. be sure of

解析：本题的含义是无论谁最后离开实验室，都要务必把所有的等关上，make sure表示务必或确保的意思，后跟从句，故本题选A。