If you ____ careful,you will fall off the tree.
问题描述：
If you ____ careful,you will fall off the tree.
A.don't be B.aren't C.are D.do be
Tom's father always makes him ___ a lot of extra homework.
A.do B.to do C.doing D.does
答
第一道,主将从现（主句用将来时,从句用一般式）选B 如果你不仔细点,就会从树上掉下去
第二道,make sb.do sth.选A