读课文《大自然的启示》选一选

A飞机    B地方      C命令     D惨祸      E超过

①  异想天开的____   ②机毁人亡的____ ③轻而易举地____

④动物栖息的____   ⑤性能优良的____

    According to a recent survey,violence did exist in schools. Students ____ (show) their fear and parents and teachers also expressed their great concern about it. ____ (expert) hope the whole society will pay more attention to the mental health of adolescents.

    Nowadays, school violence is ____ hot issue. I think this is a phenomenon（现象）, ____ calls for our great concern.We should try every effort ____ (prevent) violence happening at school for more and more students would drop out of school if their personal ____ (safe) could not be guaranteed.In fact,violence can be learned.Children learn violent behavior from adults or from ____ they see on television or on the Internet.

    If I meet with school violence,I will not answer violence ____ violence, for it will result in ____ (much、fighting.I will tell my teachers or parents about it.I think they will help me deal with it well and they will protect me from the bad guys.

    All in all, every student should behave ____ (he) and keep away from violence.

把下列各数填在相应的大括号里：

﹣（+4），|﹣3.5|，0， $\frac{\pi }{3}$ ，10%，2016，﹣2.030030003…

正分数集合：{____…}

负有理数集合：{____…}

无理数集合：{____…}

非负整数集合：{____…}．

下列各组词语，只有一个错别字的一项是(  )

一定含有Y染色体的是（　　）