一次练习中曾出现这样一道语法填空题:Unlike African elephants,after Asian elephants are captured,they are easily_(train).学生给出的答案主要有三种:trained,to train,to be trained。这引起了笔者的注意,为什么一处对被动语态的简单考查学生会给出to do以及to be done这样的错误答案呢?究 There was a grammatical fill-in in one exercise: Unlike African elephants, after Asian elephants are captured, they are easily train. There are three main answers given by students: trained, to train, to be trained. This aroused the author’s attention, why a simple examination of the passive voice students will be given to do and to be done this wrong answer?