fair enough
acceptable / understandable
what are you up to? (whatta you up to? / watchu up to?)
what are you doing?
to be free
having time to do something, to be available (not just something that costs no money)
whatshisface / whatsherface
can't remember someone's name
gotcha
I've got you / I understand
how come?
why?
I'm afraid [...]
I'm sorry but [...] / something isn't available anymore (not just "scared")
cheesy / corny
overused, unoriginal and over-sentimental things (movies, pick-up lines, songs) or persons
couldn't care less
don't care about something at all
yeah
yes (yes = impatient, sad, angry, argumentative, bad mood, irritable... OR formal)
whatever
no matter what / don't fully believe what someone has told you / giving up on something
speak of the devil!
when the person you were talking about arrives
to be up for / count me in / I'm down
wanting to do something
to grab
get (informal), want to go out with someone to do something (not just "hold")
what do you do?
what do you do for a living? what is your job?
dude / man / guys / gang / bro / girl / babe
informal ways to refer to your friend(s)
