He was so engrossed in his work that he frequently stayed up until the small hours.

他全神贯注地工作，经常工作到下半夜。

We worked well into the small hours.

我们一直工作到了午夜之后。

They were arrested in the small hours of Saturday morning.

他们在周六凌晨时分被捕。

He often works until the small hours.

他经常工作到深更半夜。

Jack has not gone to sleep when it is small hours.

杰克直到凌晨时分还没睡觉。