—There is a light.
—Please turn the light.[ ]
A. on
B. in
答案：A
用显微镜观察时，当转动物镜和移动装片，视野内的污点始终不动，则污点可能在（ ）
A．装片上
B．物镜上
C．目镜上
D．反光镜上
—________ do you play football?
—Twice a week. [ ]
A. How soon
B. How long
C. How often
