Keep a straight face
Meaning: not to laugh, to manage to stop yourself from smiling or laughing
Example: I can never play jokes on people because I can't keep a straight face. I tried to keep a straight face, but failed.
Π‘Π΅ΡΠΈΠ°Π»Ρ ΠΈ ΡΠΈΠ»ΡΠΌΡ Π½Π° Π°Π½Π³Π»ΠΈΠΉΡΠΊΠΎΠΌ Ρ ΡΡΠ±ΡΠΈΡΡΠ°ΠΌΠΈ. +1 ΠΠ΅ΡΡΡ Π² ΠΏΠΎΠ΄Π°ΡΠΎΠΊ π
Example: I can never play jokes on people because I can't keep a straight face. I tried to keep a straight face, but failed.