问题 问答题 论述题

简要说明天平应如何保养?

答案

参考答案:

⑴天平应放在平稳、牢.固、离墙的水泥台上,周围环境无振动。天平放置处附近不应有停车场,也不宜靠近公路,因汽车开动,对天平有振动而影响天平的读数等性能。如天平放在靠墙的水泥台上,那么水泥台必须和墙是一体的。

⑵天平是化验室重要的精密仪器,必须妥善保养。天平室应干燥明亮,温度波动不大且窗向北开;地面要用拧干的拖把擦拭,以免增加室内空气湿度,同时在天平内放置干燥剂。为避免天平两臂冷热不均,天平应与窗、门、暖气等热源保持一定的距离,并经常保持天平和天平台的清洁。电子天平还要求无强电磁场、高频信号的干扰。

选择题

短文改错(共10小题 ;每小题1.5分, 满分15分 )

此题要求改正所给短文的错误。对标有题号的每一行做出判断:如无错误,在该行右边横线上画一个(√);如有错误(每行只有一个错误),则按下列情况改正:

该行多一个词 :把多余的词用斜线(\)划掉,在该行右边横线上写出该词,并也用斜线划掉。该行缺一个词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词。该行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。注意:原行没有错的不要改正。

Dear Editor,

Recently, my classmates have had a heated discussion about that     

小题1:_______

we should have optional courses(选修课) in high schools. Some students were 小题2:_______

in favor of the optional courses. They say interest is the best teacher   小题3:______

and our spare time will be colorful and meaningful. Students        

小题4:_______

can not only enlarge their knowledges but also improve their abilities.   小题5:_______

However, others are against the idea, said that optional courses         小题6:_______

will take up too much time as well as energy. In addition to, some optional

小题7:_______

courses have something to do with the College Entrance Examination. They   小题8:_______

are afraid they’ll fall behind their classmates if they will take the optional 小题9:_______

courses. I’d like to take one or two of the optional courses, which, I think,

will certain benefit me a lot.                                     

小题10:______

单项选择题