汽车对道理静力作用的大小与（）无关
A、车轮总重
B、轮胎内压力
C、作用次数
D、轮胎性质
参考答案：C
---Who do you think is the man __________ first flew into space in China? --- Yang Liwei is.
A．/
B．who
C．that
D．whom
We can't ________ other countries in trade if we don't develop our nationaleconomy. [ ]
A. compete for
B. compete against
C. catch up
D. catch with
