如果阀门按操作方法来分类则可分为()。A、球形阀、球心阀 B、手动阀、电动阀、风动或液

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问题:

如果阀门按操作方法来分类则可分为()。

A、球形阀、球心阀

B、手动阀、电动阀、风动或液动阀

C、节流阀、安全阀

D、阀、蝶阀

考点:罐装制桶操作工罐装制桶操作工(初级)罐装制桶操作工(初级)题库
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根据句意,选择正确的单词。
A. office building  B. park  C. classroom  D. apartment building
1. My father works in the               
2. We can have a rest and play games in the                
3. We live in the                
4. I have classes in the                 .
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“秦王扫六合,虎视何雄哉!挥剑决浮云,诸侯尽西来。”秦王朝完成了国家的空前统一,其政治制度的基本特征是

A.权力的高度集中

B.中央政府各部门间相互牵制

C.郡县制的推行

D.“家天下”的皇位继承制

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简述审计的法律特征。

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Have you seen a yellow-and-black salamander (火蜥蜴)? How about a scarlet frog? Scientists haven’t spotted either species in more than 20 years. What happened to them? Are the creatures still out there, or are they extinct?

Those are questions that scientists hope to answer. They recently set out around the world in search of those and other long-missing amphibians. An amphibian is an animal that spends part of its life in water and part on land. Frog, toads(蟾蜍), and salamanders are amphibians.

The experts are looking for about 100 species. They are searching at least 14 countries on five continents. They will look for the salamander in North America. They hope to find the scarlet frog in South America. They’re also looking for species in Africa, Asia and Australia.

Scientists are hopeful that they’ll find the amphibians—and soon! If the creatures are out there, they may need help. Many amphibians are endangered. The animals face many dangers including pollution and diseases. People cut down the forests where they live.

“If researchers can find the missing creatures, they might be able to figure out how to save them,” explains expert Robin Moore. He began searching for the amphibians earlier this month.

“This search will tell us a lot about how amphibians are doing,” Moore told WR News. “I don’t know what we will find, but that makes the search even more exciting.”

Lost in the Wild

Scientists’ hunt for missing amphibians is under way. Read about some of the species they hope to find.

Turkestanian salamander

This salamander is a mystery to scientists. Experts found a few of them more than 100 years ago, but none have been seen ever since.

Gastric brooding frog

Experts first discovered this frog in 1914 in eastern Australia. It may be extinct because of disease and habitat loss.

Rio Pescado stubfoot toad

Last sighting: 1995, in South America

Scientists hope to find this spotted toad in rivers and rainforests in Ecuador. The animal faces threats including pollution and disease.

小题1: Which of the following animals hasn’t been seen for over a century?

A.Rio Pescado stubfoot toad.

B.Gastric brooding frog.

C.Turkestanian salamander.

D.Scarlet frog.小题2:It can be learned from the passage that _____.

A.the scarlet frog used to live in Africa

B.researchers have no way to save amphibians

C.the scientists will search 14 countries at most

D.Robin Moore has begun his search for amphibians小题3: Why do the scientists want to find the missing amphibians?

A.Because they want to rescue the missing amphibians.

B.Because they want to set up a scientific program.

C.Because they want to do a scientific research on the missing amphibians.

D.Because they want to publish a report about the missing amphibians on WR News.小题4: What does Moore think of the search for endangered amphibians?

A.It’s hopeful.

B.It’s interesting.

C.It’s tiring.

D.It’s dangerous.

题型:单项选择题

大多软体动物具有一些与环节动物相同的特征如螺旋式卵裂,个体发育中具面盘幼虫。()

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