问题 选择题

下列环境问题与空气污染没有关系的是(  )

A.酸雨

B.臭氧层空洞

C.白色污染

D.温室效应

答案

答案:C

阅读理解

阅读理解。

     People know the dangers of fires. It's good for a family to learn how to prepare for a fire. Here are some

suggestions.

     Put a smoke alarm in the house. Smoke from a fire causes the alarm to go off. The alarm makes a loud

sound. The sound tells everyone to leave the house at once.

      Make escape (逃脱) plan. They should know all the ways out of the house. If there is a fire, everyone

follows the plan to get out. Part of the plan is to check all the windows to make sure they can be opened

easily.

     Buy fire extinguishers(灭火器) in the house. Everyone in the family should know how to use them.

     Practice for a fire. They do fire practice because they teach children about fire safety. Ever yone in the

family should know the following fire rules:

     * Don't open a hot door! The fire can grow more quickly if you open the door.

     * Stay close to the floor! Smoke can be more dangerous than the fire. The best air is near the floor

because smoke rises.

     * What will you do if your hair or clothes start to burn? First, Stop! Don't run! The fire burns faster

because of more air. Drop! Fall to the floor. Then roll! Turning over and over will make the fire go out. Put

a blanket(毯子) around you to keep air away from the fire that may still be on you. 

     There are many possible causes for fires. A wise family is ready all the time. If there is a fire, don't forget

to call 119 for help.

1. The writer advises people to do the following to prepare for a fire except that _____.

A. they prepare for a fire  

B. they make escape plans

C. they buy fire extinguishers  

D. they use electrical cookers

2. What are the right steps you should take when your hair or clothes catch fire?

A. Stop, run, roll.

B. Stop, drop, roll  

C. Run, drop, roll

D. Roll, drop, stop

3. What is the best title for this passage?

A. The Dangers of a Fire

B. The Causes of a Fire

C. Learn to Use a Fire Extinguishers

D. Be Ready For a Fire

单项选择题

(五)  多少年来,人们一直在幻想研制一种航空航天运输工具,它既能从机场跑道起飞,又能以高超音速穿越大气层进入宇宙空间,完成航天任务后再入大气层,在机场水平着陆,而经过简单维修后,短期内又能重上蓝天,重复使用几十几百次,这类既具有高超音速运输机功能又具有天地往返运输系统功能的重复使用有翼飞行器,被称之为航空航天飞机,简称空天飞机。它是一种新型运输工具,具有一般飞机和航天器所没有的优越性。首先,与普通运输客机相比,它能够以更高速度在大气层上层(或近宇宙空间)机动飞行,从而大大缩短远距离运输的时间,如德国桑格尔空天飞机(第一级改进型)由法兰克福经洛杉矶飞至东京仅需3小时15分钟,美国“东方快车”由华盛顿飞至东京仅需2小时,而由欧洲飞至澳大利亚仅需1小时。再者,与以往的一次性使用飞船和多次部分重复使用航天飞机相比,它在重复使用性、机场水平起降能力,利用大气层能源、灵活机动性、发射操作费用、可维修性和复飞间隔时间等方面均有大幅度改进。如其重复使用次数可增至50至数百次,发射(运输)费用仅相当于运载火箭发射费用的三分之一(甚至十分之一或二十分之一),大型航天飞机发射费用的五分之一,比起用火箭发射小型航天飞机的费用也要降低10-30%。再如复飞间隔时间,空天飞机一般在着陆后数小时或略长时间内即可重新起飞。这是航天飞机所无法做到的。因此,空天飞机有着十分广阔的发展与应用前景,不仅可以进行全球性的高超音速运输,而且可以完成各项成本较低、效益较高的航天运输使命,为空间站往返运输人员和货物,执行各种航天军事任务。展望21世纪,它必然会成为遨游于大气层与宇宙空间的骄子。

分析有误的一项是( )。

A.普通飞机从华盛顿到东京将会超过2小时

B.空天飞机主要以载人运输为主

C.航天飞机也能完成天地往返,但完成下一次航行,要进行大量部件更换

D.空天飞机的成本及用途,决定了它在21世纪有着十分广阔的发展与应用前景