how do i force quit combat arms

its just a simple noob question i need to know >..> my laptop freezes on combat arms too much and i dont wanan restart everytime. alt+f4 isnt working for me btw.... anyother way?
ty in advance

Find Computer External Shut Down Button, Hold It for 5 secs, When it emits a purring noise and everything goes dark, push it once more, that'll satisfy both of your needs, enjoy.

that shuts down the computer doesnt? O.o