属于根内固位体的是（） A.嵌体 B.甲冠 C.套筒冠 D.铸造全冠

What was the highlight *of the May Day? It was Hangzhou Bay Bridge*, which opened on that day.       

It is 36 kilometers long and the world’s longest cross- sea bridge. It begins at Jiaxing, crosses the East China Sea, and end at Cixi, about 70 kilometers from Ningbo. It will reduce* the driving time between Shanghai and Ningbo by about two hours.

A great number of the workers started to build it on November 2003, and ended in June 2007. Now the bridge has become famous. About 40,000 vehicles *can cross the bridge each day at first. This will be added to 100,000 vehicles a day in 2026. During the May Day holiday, many car owners came to the bridge as well as tourists on coaches*. So many people wanted to see the bridge with their own eyes.

As a shortcut *between Zhejiang and Shanghai, the bridge will not only improve traffic but also help economic *development in the Changjiang River Delta.

“People enjoy working in small cities like Cixi but living in big cities like Shanghai,” said a man. “With the help of the bridge, they can leave Shanghai for Cixi in the morning and go back in the afternoon. They only need to drive for about one and a half hours.”

小题1:Hangzhou Bay Bridge opened________.

A．in November, 2003

B．in July, 2007

C．on May 1, 2008

D．on March 1, 2008小题2:It took about ___________ to finish building the bridge.

A．three years and a half

B．two years and a half

C．three years

D．four years and a half小题3:Which city is not mentioned in the passage?  ___________.

A．Cixi

B．Ningbo

C．Hangzhou

D．Shanghai小题4:The passage can most probably be found in _____________.

A．a text book

B．a magazine

C．a newspaper

D．a movie poster

逆转录是指（）。

A．以RNA为模板合成RNA

B．以DNA合成DNA

C．以DNA合成RNA

D．以RNA合成蛋白质

E．以RNA为模板合成DNA

简述学生学习的内容。

请简述CIPS法的操作步骤。

屏蔽泵流量过小会导致（）

A、电流过载

B、轴承损坏

C、压力升高

D、轴承检测器失灵