问题 多项选择题

颈椎病的体征可有 ()

A.颈椎牵伸试验阳性

B.臂丛牵拉试验阳性

C.低头试验阳性

D.仰头试验阳性

E.屈颈试验阳性

答案

参考答案:A, B, C, D, E

阅读理解

Now, are you changing your living habits to have a low carbon life? Here are some strategies (策略) for you.

Strategy One

●Each week, choose one day when you don’t eat meat. Meat takes up lots of energy because it takes a long time to produce. And animals must be fed on farmed plants, which could be used to feed many more people.

Strategy Two

●Only buy the amount of food you need. When you buy food, go local rather than imported (进口的), and get fresh vegetables instead of frozen.

Strategy Three

●Make sure you keep the things such as paper and plastic bottles separate (独立) so that they can be recycled. There are places where you can recycle batteries. Make sure you find them.

Strategy Four

●Take showers rather than baths and reduce your shower time by two minutes. This will save water and give you an extra two minutes in bed.

Strategy Five

●Buses and trains are better than cars, but walking or cycling is better still. It’s also better for your health and cheaper. It can even be quicker than sitting in a car at rush hours in a busy city. For long distances, coaches are better than trains.

Strategy Six

●Try to buy good, long-lasting products even though they may cost a little more. A small screen TV is better than a big screen. Keep your electronic products one year longer than you would usually have.

小题1:What does the underline phrase “low carbon” in paragraph one mean?

A.便宜

B.低碳

C.高效

D.舒适小题2: According to the passage, which of the following is WRONG?

A.When we produce the meat, we need to take up lots of energy.

B.Taking showers in less time will help for saving the water.

C.When you go for a long-distance trip, you’d better drive your own car.

D.Buying the long-lasting products is a good idea to have a low carbon life.小题3: What’s the purpose(目的) of the passage?

A.It helps to know walking is one of the low carbon lives.

B.It helps to realize how important it is to have a low carbon life.

C.It advises to save water and electric to have a low carbon life.

D.It advises to kick some bad habits and have a low carbon life.

阅读理解与欣赏

阅读下文并完成问题。

地球的外衣——大气

  地球被一层厚厚的空气包围着。这层空气好像地球的外衣,在科学上叫大气层。

  大气层非常厚,在靠近海面的地方十分稠密,越往高越稀薄,在海拔6到7公里的地方,空气的密度就减少了一半;在500公里的高度,大气已经十分稀薄。

  大气层可以分成好几层。每一层都有不同的特点。

  紧贴地面的一层叫对流层,大约11公里,这一层的空气最稠密,总重量占全部大气重量的四分之三还要多。在这一层里,离地面越高空气温度越低,每升高一公里,温度差产多下降摄氏六点五度,低处热,热空气就往上升;高处冷,冷空气就往下降,这就形成了对流,所以这层空气叫对流层。

  空气对流就形成了风。再说,对流层里有大量的小蒸气和灰尘之类的微粒,因而会形成云、雾、雨、雪。刮风下雨是对流层经常发生的现象。

  对流层以上是平流层。这一层的顶部离地面大约80公里。在平流层里,高层和低层的大气温度几乎没有变化,差不多都是摄氏零下五十六度,因而空气没有上下方向的对流,所以叫平流层。由于平流层里的水蒸气非常少,没有云雨等现象,所以适宜飞机飞行。

  从平流层往上,直到800至1000公里的高处,是电离层。这里的空气受到宇宙射线和阳光紫外线的强烈照射,分子被电离成带电荷的离子,所以叫电离层。电离层可以反射无线电波,给无线电通讯带来好处。电波沿地面只能传播100公里远,通过电离层反射回来,可以传送2000公里外,晚上,我们能听到远方的电台广播就是这个原因。

  电离层还会产生一种美丽的自然现象,就是极光。极光是太阳射来的电子流跟电离层中稀薄的气体分子猛烈冲击引起的发光现象。电子流受地球磁场的影响,总是偏向地球南北两极,所以极光都发生在两极地带。

  在电离层以上是扩展层,因为这里离地球很远,地球的引力非常小,空气分子就经常逃离散到星际空间去,所以叫扩展层。扩展层并没有明显的边缘,几乎延伸到了3000公里以外,从这里逐渐过渡到宇宙空间。

  大气层实在是地球得天独厚的一件理想的外衣。大气层里的二氧化碳为植物提供养料。  

  地球有了这件外衣,白天的阳光才不会把地面晒得太热,夜晚太阳落山以后,才不会变得过冷,为人类创造了适宜生存的良好环境。这件外衣还象一件盔甲,可以抵挡陨石和宇宙射线、紫外线的袭击,保护我们的安全。大气层真是一件宝衣啊!

1.什么叫“大气”?什么叫“极光”?请根据文章内容分别给二者各下个定义。

①大气是 __________________________

②极光是 __________________________ 

2.简述大气层和大气层中的“平流层”的主要特点。

①大气层的主要特点是__________________________  (不超过10个字)。

②平流层的主要特点是__________________________  (不超过10个字)。

3.大气层大体上分为四层,最后一层的名称叫_________________。这四层是按____________顺序来说明的。

4.对流层中刮风下雨是经常的事,其原因:

①__________________________

②__________________________ 

5.大气层对地球的作用,除“大气里的二氧化碳为植物提供养料”一项外,还有两项作用,它们是:①_________________ ;②_________________  。(每项表达不得超过20个字)