下列哪项对中性粒细胞无趋化作用（） A.细菌代谢产物 B.坏死组织 C.阳离

I went to his party at his ________.[      ]

A. request  

B. help

C. command  

D. expression

Tom's mother is good at cooking and she knows _____ to make food. [ ]

A. what

B. how

C. why

简述条约的程序。

Ⅳ．阅读理解（共15小题；每小题2分，满分30分）

阅读下列短文，从每题所给的四选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该选项涂黑。

A

People in cities all over the world shop in supermarkets. Who decides what you buy in the supermarket? Do you decide? Does the supermarket decide?

When you enter the supermarket, you see shelves full of food. You walk in the aisles between the shelves. You push a shopping cart and put your food in it.

You probably hear soft, slow music as you walk along the aisles. This may be an attempt to please you, so you will enjoy shopping. Some supermarkets want to increase their profits by playing soft and slow music, because the slow music makes you walk slowly and you have more time to buy things.

Fresh fruit and vegetables are usually put near the entrance. When you arrive at the supermarket, you concentrate on the kinds of fruit and vegetables you need first. Once you've got that out of the way, you can relax and do the rest of the shopping without any hurry. Besides, if you see fresh goods first, it gives you a "feel good" impression of freshness, so you can not help spending your money.

Maybe you go to the meat department then. There is some meat on sale, and you want to find it. The manager of the supermarket knows where customers enter the meat department. The cheaper meat is at the other end of the meat department, away from where the customers enter. You have to walk past all the expensive meat before you find the cheaper meat. Maybe you will buy some of the expensive meat instead of the meat on sale.

Most of the food in supermarkets is very attractive. It all says "Buy me quickly!" to the customers. The fresh fruit and vegetables say "Buy me quickly!" as you walk by. The expensive meat says "Buy me quickly!" The supermarket tells you what to buy.

56. Some supermarkets play soft, slow music because it ________.

A. can help customers get the things they want

B. makes customers walk slowly and buy more

C. can make customers relaxed and happy

D. can tell customers exactly where to go

57. The manager knows ________.

A. where customers come from    B. which customers like slow music

C. where fresh meat should be put  D. which customers like cheap meat

58. When walking past the expensive meat, the customers will _______.

A. possibly buy some                     B. pay no attention to it

C. look for some cheap meat              D. feel uncomfortable

59. If you see fresh goods first in the supermarket, ________.

A. you know where to get things   B. it brings you good luck

C. it makes you spend less money  D. you’ll get a fresh impression

60. Supermarket managers make the food attractive so that ________.

A. the customers will buy more              B. it looks very expensive

C. the customers come often                D. it seems cheap and fine

下列何种情况可能影响大翼防冰活门的工作（）

A.在空中油门杆的位置

B.在空中过热电门的位置

C.襟翼位置

D.在地面油门杆的位置