文章大意:这是一篇说明文。主要介绍了“暴风雨前的平静”这个表达通常用来描述在非常紧张的情况或紧张的争吵之前的一段和平时期。英国水手在17世纪末发明了这个短语;他们注意到,在某些风暴来临之前,海洋似乎会变得平静,风也会减弱。然而,科学给我们解释了其中的原因。
The expression “the calm before the storm” is usually used to describe a peaceful period just before a very stressful situation or a tense argument. British sailors invented the phrase in the late 1600s; they noted that before certain storms the seas would seem to become still and the winds would drop.
Science has given us the reason. According to US website HowStuffWorks, a calm period occurs because many storms, tornadoes and hurricanes draw in all the warm and humid (湿热的) air from the surrounding area. As this air rises into the storm clouds, it cools and acts as “fuel for the storm, like petrol in a car”. Once the storm clouds have taken all the energy they can take from the air, the air is pushed out by the top of the storm clouds and falls back down to ground level. As the air goes down, it becomes warm and dry. Warm and dry air is stable(稳定的), so once it covers an area, it causes a calm period before the storm.
The Weather Network has a tip for working out how far away a storm is. First count how many seconds there are between a flash of lightning and a clap of thunder, probably three seconds equal one kilometer. So, for example, if you count nine seconds, the storm is about three kilometers away. A good method is that if your count is below 30 seconds, you should seek shelter straight away.
However, due to the complexity(复杂性) of storm system, not all storms take place after calm. Given the right conditions, some storms announce themselves with heavy rain and strong winds.
So, you’d better keep yourself updated with weather reports for any predictions regarding a coming storm in your area. That’s the most reliable way to predict the storm.
32. What is the main idea of Paragraph 2?
A.How the storm takes its energy. |
B.Why a peaceful period happens before some storms. |
C.Why storms, tornadoes and hurricanes are different. |
D.What danger storms may cause. |
33. If you count 12 seconds between a lightening flash and a thunder clap, how far is probably the storm?
A.Three kilometers away. | B.Four kilometers away. |
C.Five kilometers away. | D.Six kilometers away. |
34. What is suggested to predict a coming storm?
A.Rely on your personal experience. | B.Stay at the shelter all the time. |
C.Follow the latest forecast. | D.Keep yourself in your area. |
35. What can we learn from the text?
A.Heavy storms don’t usually last long. |
B.Weather reports often fail to predict a storm. |
C.Storms have a big influence on our life. |
D.It is usually, but not always calm before a storm. |