回答

・at a point in time
・at which time

「～的時候」在英語中可以用 at a point in time 或 at which time 來表達。

I first came abroad at point in time, I couldn't speak English at all.
（我初次來到國外的時候，完全不能說英語。）

We started this business at which time, the industry was pretty small.
（我們開始這項業務的時候，這個行業還相當小。）

有幫助｜0