第三问请详解.前面两问可以忽略9．今有硫酸和盐酸的混合物20克,往溶液中逐滴加入17.1%的氢氧化钡

原则明确要求，培训过程是双向的互动交流，而不是单向的传授。

A.温故知新

B.双向沟通

C.适合

D.反应

请帮忙给出正确答案和分析，谢谢！

The______made slow but sure progress along the main street.

A．procedure

B．profession

C．process

D．procession

请帮忙给出正确答案和分析，谢谢！

Equipment and technology upgrades do not______ solve the problem either.

A．virtually

B．rarely

C．necessarily

D．practically

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挂灰烟叶形成的原因之一是()。

A.采收烟叶成熟度不够

B.烟叶变黄期烤房内温度忽低,上下波动严重,叶尖容易挂灰

C.变黄阶段低温时问过短

D.定色阶段时问过短

请帮忙给出正确答案和分析，谢谢！

Which of the following sentences is grammatically CORRECT？

A．China will further intensify bilateral, multilateral and regional economic cooperation in a long run.

B．My company is a big firm, there nearby is a big market for software in my city.

C．We will never stop less they give up at first.

D．Despite of his opposition, she worked in her own way and started her preparations.

请帮忙给出正确答案和分析，谢谢！

In recent years, both Americans and Chinese have gained sight of the original vision that brought them together. The italicized word is a(n)______in the sentence.

A．compound word

B．derivation

C．adverb

D．conjunction

请帮忙给出正确答案和分析，谢谢！