国家实验动物种子中心必须具备下列条件（）。 A.长期从事实验动物保种工作 B.有较强

过抛物线 y²=4x 的焦点作直线交抛物线于A（x₁，y₁）B（x₂，y₂）两点，如果x₁+x₂=6，那么

|AB|=[ ]

A．6  

B．8  

C．9  

D．10

阅读理解。

     Can dogs and cats live in perfect harmony in the same home? People who are thinking about adopting

a dog as a friend for their cats are worried that they will fight. A recent research has found a new recipe

of success. According to the study, if the cat is adopted before the dog, and if they are introduced when

still young (less than 6 months for cats, a year for dogs), it is highly probable that the two pets will get

along swimmingly. Two-thirds of the homes interviewed reported a positive relationship between their

cat and dog.

     However, it wasn't all sweetness and light. There was a reported coldness between the cat and dog in

25% of the homes, while aggression and fighting were observed in 10% of the homes. One reason for this

is probably that some of their body signals were just opposite. For example, when a cat turns its head away

it signals aggression, while a dog doing the same signals submission.

     In homes with cats and dogs living peacefully, researchers observed a surprising behaviour. They are

learning how to talk each other's language. It is a surprise that cats can learn how to talk 'dog', and dogs

can learn how to talk 'Cat'.

     What's interesting is that both cats and dogs have appeared to develop their intelligence. They can learn

how to read each other's body signals, suggesting that the two may have more in common than we previously

suspected. Once familiar with each other's presence and body language, cats and dogs can play together,

greet each other nose to nose, and enjoy sleeping together on the sofa. They can easily share the same water

bowl and in some cases groom (梳理) each other.

     The significance of the research on cats and dogs may go beyond pets─to people who don't get along,

including neighbors, colleagues at work, and even world superpowers. If cats and dogs can learn to get along,

surely people have a good chance.

1. The underlined word swimmingly in Paragraph 1 is closest in meaning to _____.

A. early

B. sweetly

C. quickly

D. smoothly

2. Some cats and dogs may fight when _____.

A. they are cold to each other

B. they look away from each other

C. they misunderstood each other's signals

D. they are introduced at an early age

3. What is found surprising about cats and dogs?

A. They eat and sleep each other.

B. They observe each other's behaviors.

C. They learn to speak each other's language.

D. They know something from each other's voices.

4. It is suggested in Paragraph 4 that cats and dogs _____.

A. have common interests

B. are less different than was thought

C. have a common body language

D. are less intelligent than was expected

5. What can we human beings learn from cats and dogs?

A. We should learn to live in harmony.

B. We should know more about animals.

C. We should live in peace with animals.

D. We should learn more body languages.

输卵管结扎时最易误扎的部位是（）

A.输尿管

B.阔韧带

C.圆韧带

D.子宫动脉

E.卵巢动脉

教师的风度仪表应表现为（）。

A．举止文明

B．衣着整洁

C．语言准确

D．态度亲切

E．教态自如

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