________，volunteering is both a chance to help others and a good way to develop ourselves．So you’d better make time to volunteer．
A．To my surprise
B．To be honest
C．To start with
All the class keep quiet _________ the class begins.
| A．until | B．since |
| C．as soon as | D．though |
Many people go to Tian’anmen Square to watch the national _________ rise on National Day.
| A．flag | B．flower | C．sign | D．wonder |
We will have a week _________ next month. We’re going to take a vacation.
| A．off | B．to | C．by | D．in |
My uncle bought me a book for my ___________birthday.
| A．twelve | B．twelfth |
| C．the twelve | D．the twelfth |
—Hurry up! The bus is coming.
—Wait a minute. Don’t cross the street ____________the traffic lights are green.
| A．while | B．when | C．until | D．after |