5.The research is so designed that once ___ nothing can be done to change it.

题目

5.The research is so designed that once ___ nothing can be done to change it.
A.begins B.having begun C.beginning D.begun
11.There was a terrible noise _____ the sudden burst of light.
A.followed B.following C.to be followed D.being followed
Please explain

答案

D 省略句,once it is begun
B following 接着.之后.突然的闪电之后是一声可怕的雷声.
he went into the classroom,following the students.
他跟着学生们进了教室.