I remembered the door before I left the office, but forgot to turn off the lights.
A. locking
B. to lock
C. having locked
D. to have locked
网友回答
A. locking
(答案→)B. to lock
C. having locked
D. to have locked
解析:考查非谓语动词。ACD三个选项都表示动作已经完成。只有B选项表示尚未做。句意:我记得离开办公室前要锁门的,但是却忘记了要关灯。remember doing=remember having dong=remember to have done.