YOU SAID:

トムは朝方３時まで起きてたよ。

INTO JAPANESE

トムは朝方３時まで起きてたよ。

BACK INTO ENGLISH

Tom stayed up until 3:00 in the morning.

INTO JAPANESE

トムは朝の 3 時まで起きていました。

BACK INTO ENGLISH

Tom stayed up until three o'clock in the morning.

INTO JAPANESE

トムは朝の 3 時まで起きていた。

BACK INTO ENGLISH

Tom stayed up until three o'clock in the morning.