keep something back

Từ điển Oxford Advanced Learner 8th

▪ I. ˌkeep sthˈback derived
1. to prevent a feeling, etc. from being expressed
Syn: ↑restrain
•She was unable to keep back her tears.
2. to continue to have a part of sth
•He kept back half the money for himself.
Main entry: ↑keep_derived
 
▪ II. ˌkeep sthˈback (from sb) derived
to refuse to tell sb sth
•I'm sure she's keeping something back from us.
Main entry: ↑keep_derived