分类：教育/科学-外语学习
问题：英语选择题？？如下选择题应该选项什么？请注明为什么，谢谢。一,t 
如下选择题应该选项什么？请注明为什么，谢谢。一,these young trees require ____carefully.a.looking afterb.to look after c,look afterd,looking for 二，Donn't get off the  until it___.a,Has stoppedb,stoppedc,will stopd,shall stop三，“is the radio bothering you?""it certainly is .i如下选择题应该选项什么？请注明为什么，谢谢。一,these young trees require ____carefully.a.looking afterb.to look after c,look afterd,looking for 二，Donn't get off the  until it___.a,Has stoppedb,stoppedc,will stopd,shall stop三，“is the radio bothering you?""it certainly is .i'd like it ___off"a,turning b,to turnc,turned.d,turns
回答：一选 a,像need ,want,require等词后常跟ing形式来用主动表被动.这些词后也可以用to be done 的形式.
二选 b ,这实际上是一个省略句,还原为:
 Don't  get off the bus until it is stopped.
三选 c ,这句是用动词的过去式来表被动,也可以看作是一个省略句,还原为:I'd like it to be turned off.