题干

2015年11月首架C919打飞机总装下线,标志着我国跻身飞机研制先进国家行列.

①机身蒙皮使用的是第三代铝锂合金材料.下列不属于铝锂合金性质的是____(填字母).

a.密度大 b.硬度大 c.抗腐蚀

②飞机轮胎属于橡胶制品.下列材料可用来合成橡胶的是____(填字母).

a.石英砂   b.石灰石 c.异戊二烯

③机体先进复合材料的使用率达12%.下列属于复合材料的是____(填字母).

a.钛合金    b.玻璃钢 c.普通陶瓷.

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a,c,b

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    If you thought helicopter parents were too much, wait till you learn about “lawnmower (割草机) parents”. These are the next generation of helicopter parents, who take over-parenting to the next level. Rather than staying overhead in the air, these parents actively prepare the way for their children to succeed, cushioning every bump along the way.

    Their goal is to create a soft, even surface onto which their child will proceed, free from harm and worry. They get involved before problems reach their child, sometimes even going to immoral lengths, such as writing college papers for a child who's running out of time.

    One teacher told the Irish Times: “These days you would often hear from a mother or father insisting their child be put in the top math class, for example. Self-esteem (respect) is the buzzword (popular word). They feel it would harm their child's confidence. The irony is their self-esteem would be damaged far more by sending them into a class where they can't catch up with others.

    It's not children who are out of control. It's parents. There will come a point when these children won't have parents on which to depend, and then how are they going to function? It's frightening, too, to imagine these children becoming adults and attempting to raise families of their own. They would hardly be capable of teaching independence, confidence, work ethic, and discipline to their own children if they've never learned it themselves.

    At the end of the TIME article, Gibbs shared a wonderful quote from writer D.H. Lawrence, written in 1918: “How to begin to educate a child. First rule: leave him alone. Second rule: leave him alone. Third rule: leave him alone. That is the whole beginning.