by the time 用于什么时态

“by the time +过去时”用于过去完成时。如：
By the time he got up,his parents had gone to work. 到他起床时，他的父母已去上班了。

by the time 在... 时候之前
一般用于将来完成时.
The project will have been finished by the end of this month.

过去完成时

用于完成时