马约里卡珠的宝石学性质有：（） A.折射率1.48 B.不透X射线

阅读理解。

     Mr Smith is an English teacher. He comes from America. He has a daughter. Her name is Amy, and

 she is a good engineer (工程师) in New York. Mr Smith likes traveling very much, and he can speak

 Spanish very well.  

     Now Mr Smith is in China, so he wants to learn some Chinese. He works very hard at his Chinese, and

  he goes to Chinese classes in an evening school. He has a lot of friends in China and they often help him. 

  He likes to talk with them. He tells his daughter that he can speak good Chinese, and he doesn't have any

  trouble (困难) with his Chinese at all, but the Chinese have a lot.

1. Mr Smith works in _____.

    A. a hospital

    B. a police station

    C. a school  

    D. a restaurant

2. What's Mr Smith's daughter?    

    A. A teacher.  

    B. A doctor.    

    C. An engineer.  

    D. A student.

3. Mr Smith learns Chinese _____.

    A. very well              

    B. with his daughter  

    C. every morning          

    D. very hard

4. Where does Mr Smith learn Chinese?

    A. In an evening school.        

    B. At home.

    C. In his friend's home.        

    D. In a park.

5. We know that Mr Smith is good at _____.

    A. Chinese    

    B. Spanish  

    C. Japanese    

    D. French

磨擦可以使物体带电，且电荷与电荷之间有相互作用力，即同性电荷相互吸引，异性电荷相互排斥。

阅读理解。

                                                   Coolest Hotels in the World

     Ariau Amazon Towers

    The Ariau Amazon Towers hotel lets you sleep in a tree house. Eight towers make up this hotel that

offers over 300 rooms. If you really want to get into the spirit, book the Tarzan Suite which is large

enough for a big family. You'll be thirty feet up in the air and can travel between the towers through their

wooden walkways.

     Prices: starting at $300 one night for each person for a regular room and going all the way up to

$3,000 for the Tarzan Suite.

     For more information, visit the website: http://www.ariautowers.com

The Ice Hotel

     Every winter in Jukkasjarvi, Sweden,a special kind of hotel called the Ice Hotel is built. Each year,

worldfamous artists are invited to design and produce works of art from the ice, many of which can be

found in the rooms. You'll have your choice between hot or cold rooms, but you will be well advised to

stay at least one night in a cold room for a true experience.

     Prices: starting at $318 one night for each person for either a cold room or a warm one.

     For more information, visit the website: http://www.icehotel.com

Propeller Island

    Propeller Island City Lodge is a very special hotel that was designed by a German artist. Each room

provides you with the possibility of living in a work of art. Every single piece of furniture in the thirty

rooms of the hotel has been handmade and each room is completely different. You'll be able to choose

a room based on your own personal tastes.

    Prices: starting at just $91 a night, and an additional (另外) person for only 20 extra dollars.

    For more information, visit the website: http://www.propellerisland.com

For information about other cool hotels in the world, visit the website: http://www.bahamabeachclub.com

1.What is special about the Ariau Amazon Towers hotel?

A. You can sleep in tree houses.    

B. You can choose any of the towers.

C. It is designed for big families.

D. Every room has a walkway.

2. For two persons spending a night in one of these hotels, they have to pay at least ________.

A.$111      B.$182    

C.$600   D.$636

3.Which website should you visit if you want to find out whether there exists a hotel under the sea?

A. http://www.icehotel.com        

B. http://www.ariautowers.com

C. http://www.propellerisland.com

D. http://www.bahamabeachclub.com

4. Which hotel would invite artists to come to work every year?

A. Propeller Island City Lodge.

B. Ariau Amazon Towers.

C. The Ice Hotel.

D. Bahama Beach Club.

会阴切口有感染者拆线应（）。

A．3天拆线

B．4天拆线

C．5天拆线

D．7天拆线

E．提前拆线

布置PLC系统电源，应注意哪些问题？