He was working quietly, with all his attention _______ on the task.

The earthquake in Yushu _______ roughly one month before the second anniversary of the earthquake in Wenchuan.

It is the first time that a developing country _______ the Expo, described as the Olympic Games of economy, science and technology．

— Have you ever visited the Opera House?
—Yes．When I was in Sydney, I ______ it twice．

Now if you _____ excuse me, I think I’ll be ____ my way.
A. will; in   B.will; on   C. can; by   C. can; in

—Where have you been all day?
—I _________ some former classmates and I couldn`t get back until it was dark.

.—Did you receive my letter?
—I received one just as I _________

．— I ____ to your birthday party last Sunday.
— Unfortunately, you were out on business.

— Joan was badly injured in the accident yesterday and she was sent to hospital.
— Oh, really? I ____. I ____ visit her.

—Is Paul playing basketball for his school?
—Well, he __ .But he has given it up and switched to playing volleyball .
A  is      B  was      C  has       D had