The earth is our home. We must _____ it clean.[ ]
A. change
B. sweep
C. keep
D. build
答案:C
小儿哮喘发病的主要内因是
A.外感六淫之邪
B.嗜食酸、甘、咸、腻
C.胎禀不足与伏痰
D.接触异常气味
E.活动过度,情绪激动