the manager left his office after he had finished his work为什么是after 不是until\before\if

the manager left his office after he had finished his work为什么是after 不是until\before\if
the manager left his office after he had finished his work
为什么是after 不是until\before\if

the manager left his office after he had finished his work为什么是after 不是until\before\if
如果要用until 的话,前面得加一个did not.
until可用作介词或连词,意为“到……时候为止”、“到……时候才”或“在……时候以前不”.什么情况下表达什么意思,关键要看（主）句中的谓语动词是终止性动词还是延续性动词.
1. 如果（主）句中的谓语动词是终止性动词,应采用“... not ... until ...”结构,意为“……到……时候才……”.例如：
You mustn’t eat anything until you see the doctor.
看过医生之后,你才能吃东西.
Don’t get off the bus until it has stopped.
车停稳了以后再下车.
2. 如果（主）句中的谓语动词是延续性动词,那么谓语动词用肯定式或否定式,它们所表达的意思有所不同.
1） 如果谓语动词为肯定式,则until译为“到……时候为止”.例如：
I watched TV until she came back.
我看电视一直看到她回来.
2） 如果谓语动词为否定式,则until应译为“到……时候才”,即“在……以前不”.例如：
I did not watch TV until she came back. （= I began to watch TV when/after she came back.）
直到她回来我才开始看电视.
这句话中left 就是终止性动词,所以用until 的话,前面得用否定形式.

经理在完成了他的工作之后就离开了他的办公室
until（till)意思是：直到~~，放在动词后面，常用词组有：not~~until~~~意思是直到~~~才~~~,例如:I walk until down this street.我沿这这条街一直走。
after意思是：~~过后，例如：after sclool放学后