下列熟悉的物质中属于纯净物的是[ ] A．汽水 B．酒精 C．食醋 D．碘酒

Our town has a big zoo. There are a lot of animals in it. There are some tiger and two lions. They eat a lot of meat everyday.

There are also two big elephants and a baby one. I want to ride one of them, the elephants are tame and kind, They eat a lot of grass every day. The elephants like children, because sometimes Children give them bread and bananas, elephants like bananas very much.

In our zoo there are also brown bears and white bears. They stand on their hind legs. Hold up, their arms and ask for food. They like cakes very much. There is a good place for children. They can ride horses and donkeys(驴子) and watch the monkeys there. The monkeys are very funny. They climb up ropes(绳) again and again and play  with each other like small children. They love apples, bananas and bread.

根据短文内容选择正确答案。

小题1:How many elephants are there in the zoo?

A．one

B．Two

C．Three

D．we don’t know小题2:What kind of animals eat bread and bananas?

A．Lions and tigers

B．Elephants and monkeys

C．Bears and donkeys

D．Elephants monkeys and monkeys小题3:What does tame mean?

It means       .

A高大的    B强壮的    C野生的      D驯服的

小题4:What’s color are the bears?

A．black

B．red

C．brown

D．brown and white小题5:Which of the following is wrong?

A．Tigers and lions are much stronger than elephants.

B． Both tigers and lions eating meat.

C． Bears can stand up like a man ask for food with their hands.

D． Children like monkeys because they are very funny and they are jumping and running all the time.

— Tomorrow ____ my birthday. I'd like you and Jane to come.

— I'm not sure if she ____ free. [ ]

A. will be; is

B. is going to; is

C. is; is

D. is; will be

压力蒸汽灭菌效果监测的直接指标是

A．仪表可靠性的检查

B．化学指标的检查

C．操作步骤检查

D．生物指标检查

E．仪器性能检查

英国剑桥大学的查尔斯·古达特说，人类是在地球的最后两次冰河期之间开始褪毛的。在地球气温全面上升之后，人类祖先就向北迁徙，同时为了两性喜好的选择，开始失去了覆盖在身上的毛。而在冰河期再次到来之后，人类只好再度南迁。然而借以阻挡太阳灼晒的毛的失去却使他们面临着新的生存难题。于是，各地的人就逐渐演化出至少四种肤色的人种。因此，查尔斯认为，地球上所有人种的共同祖先，必然是在可免受热带烈日灼晒之苦的高纬度地区进化而来的。在南迁之后，因环境的不同，才逐渐出现了不同的肤色。

然而另外两种较为普遍的起源说与他的理论却大相径庭。一种认为，人类是分别在世界各地各自演化出来的；另一种认为，人类最早起源于非洲，然后迁徙到世界各地。至于人类褪毛的原因，他们则认为无非是为了能在热带的烈日下凉快一些。目前科学界所公认的一种说法是，人类生活在热带时，毛皮不利流汗散热，这就需要大面积光滑无毛的皮肤。因此人类的毛大约是200万年前，由森林往平原移居时逐渐褪尽的。

对第二自然段的“他的理论”中的“理论”理解正确的一项是（）。

A．人类起源的理论

B．人类起源理论中的人类褪毛的理论

C．人类褪毛的理论

D．人类褪毛理论中的人类起源理论

丝绸之路畅通前中外贸易的特点是（）。

A.民间性

B.不经常性

C.政府推动

D.边境辗转性