1929—1933年美国经济危机的原因中不包括: A 阶级矛盾的激化 B 股票投

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问题:

1929—1933年美国经济危机的原因中不包括:

A 阶级矛盾的激化                B 股票投机猖獗

C 生产和销售额矛盾加剧          D 贫富差距不断扩大

考点:危机席卷资本主义世界“自由放任”政策的失败(胡佛)虚假繁荣的幻灭空前严重的的资本主义世界经济危机
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患儿,4岁。胸闷憋气,神疲乏力,时觉心前区疼痛,活动后诸症加重。2周前曾患流行性腮腺炎。查心电图:二度Ⅱ型房室传导阻滞。为明确诊断,下列最有意义的检查是()

A.血常规

B.血培养

C.血病毒分离

D.血沉

E.血心肌酶

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比较英法两国的政体两国政体最主要的区别是(    )

A.国家权力机关和国家元首的产生方式及其职权范围不同

B.所体现和服务的国体不同

C.实行的政党制度不同

D.资产阶级革命的历史背景、阶级力量对比和政治传统不同

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All across California, honeybees are flying away from their hives(蜂箱) and dying. Empty hives are causing a lot of worry about some important food crops.

Bees give us a lot more than delicious honey. They are pollinators(授粉者)—they enable plants to produce the fruits and nuts we enjoy by carrying pollen from one plant or flower to the next. The wind pollinates oats, corn, and wheat, but many other plants (like apple and cherry trees and melon vines) depend on insects, bats, and birds. In the U.S., millions and millions of bees kept by human beekeepers fly around doing a lot of this important work for food crops. “Bees are worth protecting because their work adds so much to our diet,” says Dr. Jeff Pettis of the Bee Research Laboratory.

California’s almond (杏仁) crop alone depends on about half the bees in the country. But now the almond crop and many others could be in trouble with so many bees dying.

Researchers at government and university labs all over the country are trying to figure out why so many bees are dying. However, bees are hard to study. Most die away from the hive, so researchers don’t have dead bodies to examine. And when researchers return to a hive after two weeks, about half the bees they studied on their first visit will be dead, replaced by new ones in the natural life cycle of bees. “It isn’t like studying a large animal like a cow that doesn’t move around much and is easy to find out in the cow field,” says Pettis.

Researchers have some ideas about what could be affecting bee health. They could be sick from poisons widely used to kill insects, or they might not be getting enough good food to stay strong. Also, tiny insects called mites feed on bees. “A virus or bacteria could also be doing the killing.” explains Pettis.

小题1:What is Paragraph 2 mainly about?

A.The wind helps pollinate.

B.Bees are important in food crops.

C.Bees give us a lot of delicious honey.

D.Cherry trees are pollinated by bees.小题2:Bees are hard to study because ____________.

A.they move around too much

B.new bees soon replace all the bees studied by researchers

C.they are too tiny

D.they never return to hives小题3:What could cause so many bees to die?

A.Poisons to kill birds.

B.Eating too much.

C.Large insects.

D.Some virus.小题4:What can we learn from the article?

A.A large number of bees have died in the hive.

B.Without bees, some foods would disappear from our diet.

C.Only researchers in California want to know what kills bees.

D.Large animals are easier to study than tiny insects.

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狗脊净制去毛时应()

A.刷去毛 

B.燎去毛 

C.烫去毛 

D.挖去毛 

E.撞去毛

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