单项选择题
Laser-doppler radar ()
A. makes use of microwaves B. measures the movements of a spaceship by means of light beam C. makes use of sound waves D. Both A and B
单项选择题 No matter how hard he worked, ()
单项选择题 They have two teams, and () have a good chance of winning.
单项选择题 He is sitting () of the car with the driver.
