The reserch is so designed that once ___ nothing can be done to change it.A.begins B.having begun C.beginning D.begun 为什么选D?
问题描述:
The reserch is so designed that once ___ nothing can be done to change it.
A.begins B.having begun C.beginning D.begun
为什么选D?
答
一般过去时表被动,一旦开始就无法改变。
答
从句是过去时 所以要用begun 这个过去式
答
research 被动begin:that once (省略了the research is) begun nothing can be done to change it.
答
begun (having been begun) 形容 the research