why do off days past so quickly and work days crawl so slowly?

hm.. someone downstairs is singing the happy birthday song.
for the 10th time in half an hour!
it makes me wonder if its a human or a radio singing the happy birthday song.

i sing one time tired already.
omg.. the singing is still on going while i m typing this post.
irritating leh.. i can hear it so super clearly!
and its a everyday thing sia.