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问题 选择题

下列叙述错误的是（　　）

A．分子都是由原子构成的

B．原子如果得到或失去电子就变成离子

C．在化学变化中分子可以分解，原子也可以分解

D．原子中原子核与核外电子的电量相等，电性相反，因而原子不显电性

答案

A、分子都是由原子构成的．A叙述正确；

B、原子通过得到或失去电子，就变成带电的原子，带电的原子属于离子．B叙述正确；

C、在化学变化中分子可以分解，原子不可以分解．C叙述错误；

D、原子中原子核带正电，核外电子带负电，电量相等，电性相反，因而原子不显电性．D叙述正确．

故选C．

完形填空

阅读下面的短文，按要求完成所给任务。

Reading is a very good hobby for all the students. You can know much about the world ①_____ the help of all kinds of books. I’m sure everyone has a favorite subject. For example, some are interested in animals, some in history, and some are interested in literature. Mine is science. I like ②___it___ because it’s fun and educational.

My favorite novel is Around the World in Eighty Days.③It was written by Jules Verne ,a French writer. Jules Verne was regarded as father of Modern Science Fiction because he devoted(奉献) himself to literature and wrote several ④well–known scientific romances.

The exciting story of Around the World in Eighty Days tells us about an English gentleman whose name is Mr. Phileas Fogg , He travels around the world in eighty days. From the story, we can see the writer’s love for the sea, traveling and adventure(冒险).In fact, they played an important role in his life. ⑤多亏了the writer’s imagination, language skills and scientific and geographical(地理的) knowledge, we can feel as if we were there when we read the story.

小题1:根据上下文写出①处所缺的单词。

小题2:写出②处划线单词所指代的内容。

小题3:将③处改为主动语态。

Jules Verne, the French writer _________ the novel Around the World in Eighty Days.

小题4:写出④处划线单词的同义词。

小题5:将⑤处划线汉语翻译成英语。
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单项选择题

交换机（Switch-1）怎么将数据发送到MAC地址为00b0.d056.efa4的主机（）。

A、它会丢弃该包，因为MAC地址表中没有该地址

B、除了生成该数据的端口，它会从各个端口广播该数据

C、除了生成该数据的端口，它会从各端口发ARP请求

D、它会发送到默认网关
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