Many people like the feeling of the gentle wind in spring. Many like to see the

Many people like the feeling of the gentlewind in spring. Many like to see the falling leaves dancing in the wind inautumn. But sometimes, when the wind becomes a storm, it can be verydestructive (毁灭性的).

A series of such storms struck the US lastmonth and caused very serious damage and human pain.

Every year, major storms cause manyproblems around the world. There is nothing people can do to stop thesepowerful forces of nature. But new techniques are helping scientists to predicthow, when, and where big storms will happen. The more exact scientists’warnings are, the better people can prepare for the storms.

Predictions are improving. “We’ve gottenbetter over the years, especially the last few years,” says Phil Klotzback, ascientist at an American university. How is a storm formed? Even if scientistsknow where a storm will happen, winds can suddenly change, carrying the stormto a new direction. “For a hurricane to happen, conditions have to be justright,” Klotzback says.

First, the ocean water needs to be warmenough so that it evaporates and rises into the air. As it rises, theair containing drops of water cools and turns back into liquid. This processgives off heat. This produces energy like an engine that causes winds toincrease. It drives the formation of a hurricane.

If wind speeds reach 40 miles per hour, thesystem is called a “ tropical storm”, and it gets a name. At 75 miles per hour,it becomes a hurricane. Hurricanes that hit the US start when a thunderstormforms off the coast Africa. Storms also develop over tropical waters in otherparts of the world.

On average, 60 or 70 storms form off Africaevery year. About 10 of them get names. There are usually about six hurricanes.Two tend to be very big, with winds of 115 miles per hour or a bit higher.

The hurricane season lasts from June toNovember. Ninety percent of all hurricanes hit in August, September andOctober.

1.According to the text, hurricanes usually________.

2. The underlined word “evaporates” (inParagraph 5) probably means “________”

3.Which of the following about theinformation of a hurricane is the correct order?

a. The ocean water evaporates and goes intothe air.

b. Heat creates energy and causes winds toincrease.

c. The vaporcools.                        

d. The ocean water is warm enough.

e. The vapor changes back intoliquid.       

f. This course gives out heat.

试题答案

【答案】

1.B

2.D

3.C

【解析】略