对于磁场和磁感线,下列说法中错误的是: [ ] A.磁场的基本性质是对放入其中的

题型:选择题

问题:

对于磁场和磁感线,下列说法中错误的是: [ ]

A.磁场的基本性质是对放入其中的磁体产生磁力的作用

B.磁场看不见摸不着,但我们可以借助小磁针的偏转和指向来判断

C.磁感线是磁体周围空间实际存在的曲线

D.在磁体的外部,磁感线都是从磁体的北极出发回到南极

考点:磁场、地磁场磁感线及其特点
题型:选择题

CPU接收中断类型码,将它左移( )位后,形成中断向量的起始地址,存入暂存器中。

A.1

B.2

C.3

D.4

题型:选择题

Sydney—Mobile phone has become a problem for middle schools. Some middle schools in Australia have banned(禁止)students from carrying mobile phones during school hours.

Mobile phone use among children has become a problem for the school this year. Several children have got mobile phones as Christmas gifts, and more students want them.

Mary Bluett, an official, said mobile phone use is a distraction(分心)to students during school hours and it also gives teachers so much trouble in their classrooms. Teachers were also saying that sometimes students might use phone messages to cheat during exams.

She said some schools had tried to ban mobile phones. Some parents felt unhappy because they couldn’t get in touch with their children.

Many teachers said students should not have mobile phones at school, but if there was a good reason, they could leave their phones at school offices. They also said there were many reasons why the students should not have mobile phones at school: they were easy to lose and were a distraction from studies.

Many people say that they understand why parents would want their children to have phones, but they think schools should let the students know when they can use their mobile phones.

小题1: Some middle schools in Australia have banned students from carrying mobile phones ____________.

A.because they are students

B.when they are at school

C.because they are young

D.when they are free小题2: We know from the passage that some children get mobile phones from ____________.

A.the makers and sellers

B.some other strangers

C.their parents and friends

D.some mobile phone users小题3: Some parents felt unhappy because they couldn’t        during school hours.

A.get in touch with their children

B.leave their mobile phones

C.help the teachers with their work

D.use their mobile phones小题4:The underlined word “they” in the fifth paragraph refers to ____________.

A.many teachers

B.some messages

C.mobile phones

D.some students小题5: The topic mainly talked about in the text is ____________.

A.why the students should not use mobile phones in some Australian schools

B.when the students of some Australian schools can use their mobile phones

C.whether the Australian students can have mobile phones at school

D.how some parents feel when their children should not carry mobile phones

题型:选择题

“浓缩的都是精华”反映了()

A.酸葡萄心理

B.甜柠檬心理

C.阿Q心理

D.小辣椒心理

题型:选择题

你认为木质机的翼梁部分一般采用哪种木材()

A.桐木

B.巴尔莎木

C.松木

D.层板

题型:选择题

当盾构机盾体被注浆体凝固“箍死”时能帮助推进千斤顶松动盾构机脱困,而且还能作为曲线施工的一种辅助手段的装置是()。

A.铰接装置

B.驱动装置

C.推进装置

D.润滑装置

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