YOU SAID:

He was late so he bought me a round of drinks

INTO JAPANESE

彼は遅刻したので、私に一杯の飲み物を買ってくれました

BACK INTO ENGLISH

He was late, so he bought me a drink.

INTO JAPANESE

彼は遅刻したので、私に飲み物を買ってくれました。

BACK INTO ENGLISH

He was late, so he bought me a drink.