选择可替换划线部分的选项。

小题1:When is your birthday?

A. age                B. date of birth       C. day

小题2:How old is he?

A. How is he          B. How old is she      C. What’s his age

小题3:What time does she play basketball?

A. Where              B. When               C. What

小题4:I often have lunch at 12:00.

A. eat                 B. eats                C. has

小题5:She is 9 years old.

A. She is 8 years old  B. Her age is 9        C. I am 9 years old

钟面式百分表中盘形弹簧的作用是消除齿轮的啮合间隙所引起的______。

A．误差

B．放大

C．震动