化验作业前应洗手，着手不清洁，可能玷污（），影响分析结果的可靠性和准确性。
A、仪器C
暂无解析
Thenewspaperwillhavetoclosedownifitcannotincreaseits________considerably.
_______foralongtime,mostofthecropsinthisareadiedfromlackingwater.
Hewouldratherdiethanlivein__________.
___youlikeotheritems,kindlyletusknowandweshallbeonlytoopleasedtomakeyouoffersdirect.()
In1995,anaverageof_______ofdomestictravelerswentonsightseeinginChina.
