sing along with somebody

Từ điển Oxford Advanced Learner 8th

ˌsing aˈlong (with sb/sth) | ˌsing aˈlong (to sth) derived
to sing together with sb who is already singing or while a record, radio, or musical instrument is playing
•Do sing along if you know the words.
•She loves singing along to the radio.
related noun ↑singalong
Main entry: ↑sing_derived