柴油汽车对大气主要有那几个的污染源（）。
A、排气污染
B、曲轴箱内废气溢出污染
C、二氧化碳
参考答案：A, B
He heard someone following him,and glanced round.He ________ a dark figure in the shadows.[ ]
A. lost sight of
B. caught sight of
C. fell in love with
D. lost touch with
一定条件下，“五气”与“五志过极”均可化生
A．风B．火C．湿D．燥E．暑
