读短文，选答案。

      I'm Nancy. My birthday is August 15th. I usually get up early on my birthday because I am too excited

to sleep. My parents usually give me a birthday present. I don't go to school on my birthday, because it's in

summer holidays (假期). Usually I have a birthday party. We have a big dinner and eat a birthday cake. We

also sing, dance and watch TV at the party. In the evening, my family goes out for a walk. I always have a

good time on my birthday.

1. Nancy's birthday is in ______________.[ ]

A. spring

B. summer

C. fall

2. Nancy usually gets up early on ______________. [ ]

A. Monday

B. July 20th

C. August 15th

3. Nancy usually ______________ on her birthday.[ ]

A. goes to school

B. has English class

C. has a birthday party

4. Nancy doesn't ______________ at the party.[ ]

A. play sports

B. watch TV

C. dance

5. Nancy goes out for a walk with her ______________.[ ]

A. family

B. friends

C. classmates

涡轮流量计二次系数的作用及含义是什么？