①往Na₂SiO₃溶液中通入CO₂产生白色沉淀

②石墨是导体，晶体硅是半导体

③制玻璃过程中发生反应Na₂CO₃+SiO₂ $\underset{\_}{\underset{\_}{高温}}$  Na₂SiO₃+CO₂↑

④CH₄比SiH₄稳定．

    During holidays，Kitty usually goes to see the exhibits in many museums，such as the history museum，the art museum，the museum of science and technology and the museum of natural history．There are thousands of wonderful things in museum.There are paintings，sculptures(雕塑)，costumes(服饰)，swords(剑)，ancient animal bones and plants，stuffed animals(动物标本)and many others．It is always a good review of history to visit those museums．It is also a great way to learn more things by myself．

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下列句子中句式不同类的一项是（）

近年来,吉林省高度重视少数民族和民族地区发展,认真贯彻党的民族工作方针政策,加大对民族地区重大基础设施、重大公共服务设施、重大生态保护工程建设等方面的支持力度。上诉措施有利于 （  ）