Private cars will be required to stay off roads one out of five weekdays ____ the traffic pressure.

______ lots of times, the song doesn’t sound as nice as before.

I am pleased ______to the party ------it was so fantastic!

Don’t respond to any e-mails ______personal information, no matter ______ official they are.

 ---Do you feel like ____ out? ---No. I’d rather we _______ a taxi.

The farmers built long fences, ____ keeping the wild dogs out of them.

He ran as fast as he could _____ to catch the early bus.

Everyone in our class was working hard and doing what we could ________ a good university. 

---Can those _________ at the back of the classroom hear me ?

The news shocked the public,________ to great concern about students’ safety at school．

Michael put up a picture of Yao Ming beside the bed to keep himself ________ of his own dreams.

Not knowing his address , she had some difficulty ________ his house.

Who would you rather _______ the watch?

-- Isn’t it time you _____ down to _______ your own things? --- I’m sorry for the delay, Dad.

Many gases        in the atmosphere actually        heat energy that escapes from the Earth’s surface back to the earth.

At the news of the earthquake, the soldiers did what they could       the victims.  

Allen followed his customer across the yard and stood on the step of the house,        two shopping bags. 

Our English teacher, having explained to us how to design a project, allowed us a whole week’s preparation and then       the class. 

Every day after I went home, if not _______ from work, I will go out for a walk with my wife.

Everyone in our class was working hard and doing what we could ______ a good college.