很多高楼大厦的外墙安装玻璃墙幕，这对环境会造成（）
A、光污染
B、大气污染
C、噪声污染
D、声污染
参考答案：A
Though it is difficult, I ______ him find a job, which made him very pleased.
A．tried to help
B．managed to help
C．tried helping
D．succeeded to help
骨、关节病变或内分泌紊乱等常见于（）
A.支气管哮喘
B.支气管肺癌
C.支气管扩张
D.阻塞性肺气肿
E.肺结核
