完成句子.（共6小题;每小题1分,满分6分）

小题1: The headmaster __________ (宣布) that we would put off the sports meeting because of the weather.

小题2: Old people should be _________ (说) to politely.

小题3: Of all the __________ (发明)，which do you think is the most useful?

小题4:We’ve had several____________(分歧)，but we still get well on with each other.

小题5: I like to sing songs while  _________ a shower.( 淋浴)

小题6:.His health is___________(逐渐) improving.

医疗卫生服务中的常见危险因素不包括（）。

A、院内感染

B、责任医疗事故

C、误诊漏诊

D、医疗预防保健