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问题 选择题

只用一种试剂就可区别NaCl、Al2（SO4）3、（NH4）2CO3、Mg（NO3）2四种溶液．这种试剂是（　　）

A．NaOH

B．BaCl2

C．AgNO3

D．HCl

答案

A、向以上四种溶液中加入氢氧化钠溶液后反应现象分别为：无现象，先生成白色沉淀后消失，生成能使湿润的蓝色石蕊试纸变红色的气体，生成白色沉淀，反应现象不同，可以区别，故A正确；

B、向NaCl、Mg（NO3）2溶液中加入氯化钡溶液无现象，不能区别，Al2（SO4）3和（NH4）2CO3与氯化钡都生成白色沉淀，也不能区别，故B错误；

C、NaCl、Al2（SO4）3、（NH4）2CO3和硝酸银反应都生成白色沉淀，现象相同，不能区别，故C错误；

D、盐酸和NaCl、Al2（SO4）3、Mg（NO3）2不反应，现象相同，不能区别，故D错误．

故选A．

完形填空

On October 19，1959，the first Special English program was broadcast on the Voice of America．It was an experiment．The goal was to communicate by radio in clear and simple English with people whose native language was not English．Experts said the goal was admirable，but the method would not work．However，             ．The Special English programs quickly became some of the most popular on VOA．And they still are．

Forty years later，Special English continues to communicate with people who are not fluent in English．But during the years its role has expanded．It also helps people learn American-English．It succeeds in helping people learn English in a non-traditional way．And it provides listeners, even those who are native English speakers, with information they cannot find elsewhere.

Today，Special English broadcasts around the world seven days a week，five times a day．Each half-hourly broadcast begins with ten minutes of the latest news followed by 20minutes of feature programming．There is a different short feature every weekday about science，development，agriculture，and environment，and on the weekends about news events and American idioms．These programs are followed by in-depth(深入的)15 minutes features about American culture，history，science，medicine，space，important people or short stories．

小题1:What is the best title of the passage?(Please answer within 10 words．)

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小题2:Which sentence in the passage can be replaced by the following sentence?

(Special English has played a more important part in many areas over the years．)

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小题3:Please fill in the blank in the first paragraph with proper words or phrases to complete the sentence．(Please answer within 10 words．)

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小题4:What do you think about Special English?(Please answer within 30 words．)

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小题5:Translate the underlined sentence in the second paragraph into Chinese．

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单项选择题

有关系离泊作业安全要求，下列哪项错误（）。

A.每次系泊前，由三副会同大、二副试验对讲机以保证联系畅通

B.系泊操作时，大副在船首指挥，木匠协助；二副在船尾指挥，水手长一般在船尾协助

C.在投掷撇缆时，应先撇出后招呼，防止撇缆头伤人

D.靠离完毕，经船长同意方可离开现场
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