下面四个图象分别表示四个做直线运动物体的位移、速度、加速度和摩擦力随时间变化的规

下列叙述与化学知识相符合的是[ ]

A．汽油中加入乙醇可节省石油资源，减少污染

B．酸雨主要是由于农村使用农药和化肥造成的

C．用水灭火是因为水可以降低可燃物的着火点

D．塑料是天然有机材料，对环境没有不良影响

Many of Chinese students who have learnt English for more than ten years are still unable to speak English fluently when they meet a foreigner. They seem to have mastered the basic language structure, but a conversation in English will make them feel uneasy. They are afraid that other people might find out their mistakes.

It is not uncommon that many students, who are bad speakers of English, can write English perfectly. This proves that they are not unable to organize their idea in English. The center of the problem is that they don’t have enough practices and confidence.

Why should you be afraid? Do you fear those foreigners to whom you are speaking? Don’t be shy. They will not laugh at you just for a little mistake you make. The best to get rid of this trouble is to learn to speak by speaking more. I am sure that more practice will help you to succeed.

小题1:What’s the best topic for the passage?

A．How to speak to foreigners

B．How to write English well

C．How to organize the idea in English

D．Practice speaking English小题2:So many Chinese students dare not speak to foreigners because_________.

A．they are afraid they can’t understand the foreigners

B．they worry about making mistakes in their speaking

C．they are afraid their English is too poor

D．they don’t like speaking to foreigners小题3: In the last paragraph, the expression “get rid of” means _________.

A．do with

B．be free of

C．be afraid of

D．get into

影响节肢动物生长发育的主要环境因素是（）。

A.光照

B.温度

C.湿度

D.植被

E.地质

血窦（sinusoids）

胜利油田标准RTU COM1指示灯为（）色闪烁时说明（）

A.黄；有数据收发

B.红；有数据接收

C.黄；无数据收发

D.红；无数据发送