当时用英语怎么说？

当时用英语可以用"at that time"来表示。这个词来源于中文，在中文里它可以译作"当时"。

例句：

At that time, I was living in New York. (当时，我住在纽约。)

She was very busy at that time. (当时，她很忙。)

I didn't have much money at that time. (当时，我没有多少钱。)