If you don't know some modern lingo, you'd be considered very "out" by the younger generation... here are some i have picked up:
CMI - cannot make it: means "not up to mark"
Example: The restaurant's service is very cmi! =(
GG - good game: means "that's it!" or "die" or "gone case"
Example: I din study for my test neh, GG liao.
HTHT - heart to heart talk: means "heart to heart talk" la!! i.e. tête-à-tête
Example: During the camp, they had a HTHT or Let's have a HTHT!! *girly excitement*
BHB - buay hiao bai: means: "no sense of shame" basically saying someone is not humble, used to describe someone who overtly praises oneself
Example: He is very BHB one neh, always say he is most hamson.
Pao Toh - to tell on [someone]
Example: You pao toh me! told teacher i cheat in test!
Tai Koh - by luck
Example: *someone shoots in a 3-pointer in basketball* ai ya, he tai koh one la
imba - imbalanced: means "elite, awesome, the best, unbeatable"
Example: His singing is imba, man.
Got any more? share leh? need to stay current, if not they will say got generation gap...