题干

4种短周期元素W、X、Y、Z的原子序数依次增大,其原子的最外层电子数之和为19,W和X元素原子内质子数之比为1∶2,X2+ 和Z离子的电子数之差为8。下列说法不正确的是                                                          (   )

A:与W相邻的同主族元素形成的单质晶体中原子个数与共价键数之比为1︰4

B:元素原子半径从大到小的顺序是X、Y、Z

C:WZ4分子中W、Z原子通过共价键结合且最外层均达到8电子结构

D:W、Y、Z元素最高价氧化物对应的水化物中酸性最强的元素是Z

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A

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    In spite of so many years of education behind us, can we confidently say we understand what it feels like to be a teacher?

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    Now it can be really annoying for a teacher if someone says teaching is one of the easiest jobs around, because everyone just needs to be taught for a few hours a day. ____ However, teachers work longer to come up with ways to make the knowledge appear more interesting to students and help them learn better.

    ____ And this is a big reason why more people decide to choose teaching as a career. However, good teachers choose to make good use of the break, by enrolling (注册) themselves for workshops on teaching, classroom management, and related things.

    All teachers are not the same, as against what is widely believed. ____ Every teacher is different and has a different approach(方法)to teaching.

 ____ A teacher has meetings to attend, and is responsible for (对……负责) organizing school events. An important duty of a teacher is to prepare the progress report of each student and discuss it with his or her parents.

    In a word, teachers ought to be respected for what they do, and we should never forget their great contribution(贡献)to our success in life.

A. A teacher has many things to do rather than just teach.

B. It is true that teachers get a lot more holidays than others.

C. A good teacher is one who motivates students to overcome challenges.

D. To begin with, teachers are people who perform well in their fields of study.

E. A statement that is true for one teacher is not necessarily true for the others.

F. And common people even believe teachers are probably overpaid when their days end at 3 pm.

G. These teachers give all they can to create an ideal learning environment for their students.