单选题 —How far is it from Tianjin to Changsha?
—It is(　　)____ flight.

单选题 We were very busy yesterday, because we(　　)____ to do.

单选题 Mr. Black has(　　)strong ____ of duty.

单选题 —Excuse me, how can I get to the nearest bus stop?
—Go down this road. It’s about ____ walk.

单选题 China has ____ of more than 1.4 billion.

单选题 We called at ____ yesterday.

单选题 He has poor ____, so(　　)can’t see the words on the blackboard clearly.

单选题 ____ important to everybody.