20.—Is that Dec. 21, 2012 is the end of the world true? —Definitely not, but________must be paid to the global climate change.
----- What’s that terrible noise? ----- The neighbors ________ for a party.
We were going out for a Christmas meal together ____ the accident happened.
Jack had to call a taxi because the box was _______ heavy to carry all the way home.
He will work in a big company after he _____ the university.
He _____ his work with animals.