题目内容：

Last year，three experienced storm chasers were killed in a tornado(龙卷风)in the US，but despite this the number of people going in search of tornadoes is growing．What drives them to take risks and look for danger? The man at the wheel glanced in the back-view mirror and then slowly turned around．“Don’t put this in your program．”he said．His wife in the passenger seat laughed．He lowered the window and killed the engine．The wind rushed in from surrounding wheat fields．

Then，from behind，the sound of footsteps approached on the dirt road．It was a moment of peace after hours of speedy racing through the American grassland．There had been excited shouts about where a tornado might form and how we would be there if it did．We were crazy on the trail a moment ago．But now，everyone was very coo1．A Kansas state trooper(骑警) introduced himself through the window．There was pretended surprise when he said how fast we had been going．Really? Wow，sorry．

Val Cator handed over his ariver’s license．His wife，Amy，took the registration out of the glove box．Val explained they were storm chasers with Channel 9 News out of Oklahoma City—though it was hardly necessary．Their huge black truck has lightning bolts(闪电)and Storm Tracker 9 painted on the sides．

Val pointed to the radar on the laptop open next to him and said those red and green dots suggested a tornado could form this afternoon．The state trooper was untouched．“I've got that in my car too．”he said．People here keep a close eye on the weather．It’s part of living in the tornado alley．Every year some town or other is blown off the map by tornadoes that can reach 300 miles an hour．

Val and Amy are just two of hundreds of possibly thousands of trackers who speed around with computers and cameras hoping to catch one of these beautiful，deadly storms．I'd joined them to learn why the number of trackers keeps growing．Why are people taking real risks—beyond the steady diet of rest-stop junk food—to watch weather?

Last year，a tornado killed three of the most experienced storm chasers．It picked up and threw their car as easily as you would a piece of paper．Dozens of other chasers were hurt in the same storm．They were crowded on a few roads when the tornado suddenly expanded and ate them．Val and Amy were there that day but still，in their words，chase aggressively．

1.Why did everyone calm down after being crazy?

A. Because they reached grassland．

B. Because a tornado would come．

C. Because a trooper stopped their car．

D. Because they were cool on the trail．

2.What could show Val Cator’s profession?

A. His driver’s license．

B. The glove box．

C. The signs painted on his truck’s sides．

D. The news of Oklahoma City．

3.Which word can be used to describe Val and Amy?

A. Hard-working．    B. Adventurous．

C. Generous．    D. Humorous．

4.The passage is mainly about______．

A. a program about storm chasers

B. the possible dangers that storm chasers face

C. the most violent tornado in the US

D. some people who want to be close to tornadoes