having been done和had been done的区别All the tasks______ahead of time_英语解答

having been done和had been done的区别
All the tasks______ahead of time,they decided to go on holiday for a week.
A.having been fulfilled
B.had been fulfilled
为什么选A而不是选B?

人气：357 ℃　时间：2019-10-18 23:32:33

解答

这道题考的是独立主格
独立主格表时间用法
例句
The meeting being over,all of us went home.开完会后我们都回家了.
如果选B
时态没问题,但是两个句子都可以独立成句了,句子之间没有连词
应该后面句子有个 so 或者前面句子有个 because 等表原因结果的连词