after用法The system crashed up after halted.我忽然忘记了after的用法.请问上

这个句子可能这么说好点：The system crashed up after halting.
After 是介词,如果动词和主语是主动关系,就用doing.如果是被动关系,就用done.也可以直接接句子.
这里系统停止应该是主动关系,所以用doing.

1. 用作连词是词，它引导的时间状语从句如果具有将来意义，往往要用一般现在时来表示(有时也用现在完成时)，而不能直接用一般将来时。如：
误：I’ll tell him after you wil leave.
正：I’ll tell him after you leave (或have left). 你走了之后我再告诉他。
2. 一般说来，如果在过去某一时间内先后发生了两...

(1)介词:
(a) Please come to my house after dinner.晚饭后
(b) He ran after the bus. 追赶
(c) His mother waited for him night after night.（一个）接着（一个）
(d) It's sad to fail after all that work. 由...