clam up

US /klæm ʌp/
UK /klæm ʌp/
"clam up" picture
1.

berdiam diri, membisu

to suddenly stop talking, especially when you are expected to speak

:
When the police started asking questions, he just clammed up.
Apabila polis mula bertanya soalan, dia terus berdiam diri.
She tends to clam up when she's nervous.
Dia cenderung untuk berdiam diri apabila dia gementar.