*Offering to do something :
A: Let's go to canteen, i'm hungry
B: Oh, sure! 

A: How about going to the cinema?
B: When will we go?
A: Tomorrow morning at 8 a.m. I'll wait you at the mall's door
B: Okay!

A: Why dont you try to do it by yourself? It must be more useful, for you especially
B: I'm not sure i can do it :(
A: Please, i know you can. Believe!