Question

I't was not until he got to the office_A__he remembered ____

Answer 1

It is + 时间点 + when… 的意思是“当……的时候时间是……”.

It is + 时间段 + before… 的意思是“在……之前有一段时间”.

请看以下用例：

It was past one o’clock when he came in.他回来时已经一点多了.

It won’t be long before they understand each other.过不了多久他们就会互相了解的.

remembere to do 忘记去做某事

remembere doing 忘记做过某事

显然 这里要用 ing了