Parallel conversations are funny

Dollal, D, M and me, walking home from school:

D: We have to study this and this....
Dollal: Yeah... shit...
D: ... and we need to put away some time to write that essay.
Dollal: Oh man I almost forgot about that one...

M: Hey Dollal wait we need to buy toothpaste.

Dollal: OH MY GOD I CAN'T AFFORD THIS!!!!
M: !!?! ... it's toothpaste!?