题目内容
If you really have to leave during the meeting, you’d better leave ____ the back door.
A. for B. by C. across D. out
If someone falls off the ladder and gets seriously hurt, you’d better leave him _____ he falls and try to get help.
If you really have to leave during class, you’d better leave____ the back door.
A. for????????? B. at??????????? C. by???????? D. out?????????
