1∶2000比例尺地形图的比例尺精度是（）。A、±0.1mm B、±0.2mm C、

设全集U={a，b，c，d}，集合A={a，b}，B={b，c，d}，则（∁_UA）∪（∁_UB）=______．

嫡长子继承制是西周宗法制的核心。在这一制度下，政治权利的分配主要依据[ ]

A．血缘的远近

B．才能的高低

C．军功的大小

D．财产的多少

Do you know what really troubles me? For some reason, words with silent letters have always bothered me. For example, consider these words: know, design, island, school, wrist, naughty, and salmon. All of these words have at least one letter that is not typically pronounced, and these words are just a very small part of words with silent letters in them.

Some words are even worse, consider this word: colonel. Not only are some letters not pronounced, but letters that are not even there are pronounced.

Even foreign languages, especially French, are guilty of this needless complexity and confusion. I know there must be some main historical reasons why the words are spelled and pronounced the way they are, but that does not mean bad traditions must continue to survive. Especially if they are no longer logical.

Unfortunately, there is very little that anyone can do for it, because there’s no group of people who can change or have the right to change the English language for everyone. However, the only thing we can do is make changes in the way we talk and write in hopes that it catches on. For example, I pronounce the letter “l” in salmon on purpose to make people annoyed and to sound more different or complicated. I even pronounce colonel the correct or French way.

I can only hope these two minor changes to the English language make sense to you, and you will help to keep up these minor changes forever in your everyday life.

小题1:We can learn from the passage ________.

A．colonel is pronounced

B．salmon is pronounced

C．all the words with silent letters come from French

D．linguists will solve the problem of dumb letters小题2:Which of the following is the main reason for silent letters?

A．French language.

B．Historical reasons.

C．Some linguists

D．Bad traditions.小题3:The underlined phrase “catches on” probably means “________”.

A．becomes popular

B．gets across

C．follows the fashion

D．doesn’t fall behind小题4:Which of the following is the best title for this passage?

A．Troubles in everyday life

B．Traps in English words

C．Words with silent letters

D．Necessary changes of languages

先天性遗传异常对药物的药理学作用影响主要表现在（）

A.口服吸收速度不同

B.药物体内生物转化异常

C.药物体内分布异常

D.遗传性高铁血红蛋白还原障碍

E.以上都有可能

一松一紧的真正含义是什么？