简述光纤色散是怎样形成的？

阅读理解。

     It is difficult for parents of nearly every family to teach their children to be responsible (有责任的) for

housework, but with one of the following suggestions, you really can get your children to help at home.

     If you give your children the impression that they can never do anything quite right, then they will

regard themselves as unfit or unable persons. Unless children believe they can succeed, they will never

become totally independent.

     My daughter Mary's fifth-grade teacher made every child in her class feel special. When students

received less than a perfect test score, she would point out what they had mastered (掌握) and declared

firmly they could learn what they had missed.

     You can use the same way when you evaluate (评价) your child's work at home. Don't always scold

and you should give lots of praise instead. Talk about what he has done right, not about what he hasn't

done. If your child completes a difficult task, promise him a Sunday trip or a ball game with Dad.

     Learning is a process (过程) of trying and failing and trying and succeeding. If you teach your children

not to fear a mistake of failure, they will learn faster and achieve success at last.

1. The whole passage deals with ________.

A. social education

B. school education  

C. family education

D. pre-school education

2. The author thinks that ________.

A. there is no way to get children to help at home

B. the more encouragement and praise you give, the more responsible and helpful children will become

C. it is very difficult to make children responsible for housework

D. children can be forced to help with housework

3. The passage gives us a good suggestion about how to evaluate your child's work at home.

    That is to ________.

A. praise his success          

B. promise him a trip

C. give him a punishment      

D. promise him a ball game

4. The author advises readers to ________.

A. learn from himself, for he has a good way of teaching

B. take pride in Mary's fifth-grade teacher

C. do as what Mary's teacher did in educating children

D. follow Mary's example because she never fails in the test

5.  Having read the last paragraph, we can conclude that           .

A. pride goes before a fall      

B. practice makes perfect

C. no pains, no gains          

D. failure is the mother of success

何谓菌种复壮？如何达到菌种复壮？

《房屋建筑和市政基础设施工程施工图设计文件审查管理办法》中规定了（）。

A.施工图设计文件审查的程序

B.建设单位应当将施工图送审查机构审查

C.审查机构不得与所审查项目的建设单位、勘察设计企业有隶属关系或其他利害关系

D.建设单位对已经审查合格的施工图有自行修改的权利

E.建设单位在送审施工图时应向审查机构提供：作为勘察、设计依据的政府有关部门的批准文件及附件和全套施工图

信号机制是解决进程同步和互斥的有效工具。实现进程间的互斥时，公用变量信号的初值一般设置为 (15) ；实现进程间的同步时，私用变量初值一般设置为 (16) 。

A．-2

B．-1

C．0或资源数目

D．1或资源数目

差压式流量计是基于流体流动的（）原理，利用流体流经节流装置时所产生的（）来实现流量测量的。