轿车挡风玻璃不竖直安装，其主要原因是_______________________。
避免在司机正前方成像，影响司机视线
Though I ____ his words this time , I don't ____ him.
[ ]
A. believe in , believe
B. believe , believe in
C. believe , believe
D. believe in, believe in
吸入氧浓度为41%每分钟的氧流量是
A．3L
B．4L
C．5L
D．6L
E．7L
