When Columbus reached the New World, corn was the most widely grown plant in the Americas. This plant´s range extended from what is now southern Canada to lower South America. At that time some tribes cultivated it at sea level, others at elevation of more than 11,000 feet.

　　“Columbus had no way of knowing that corn was far more valuable than the spices (香料) and gold he had hoped to find.” said Frances

　　B. King, a professor at a university of Pittsburgh. Through human intervention, this plant has developed into several hundred races, or varieties. Their heights vary from 2 to 12 feet, and their maturity ranges from little more than 2 months to almost a year. Their ears vary not only in color, but also in size.

　　Unlike other cereals (谷類)， corn bears little resemblance to its wild ancestors. In fact, it differs from the appearance of its immediate ancestors more than any other cultivated plant known. From humble origins as a lowland grass, corn developed into the western world´s important grain. As its high yields allowed communities to grow far beyond what early agriculture could feed, most scientists viewed corn as having largely fueled pre-Columbian growth and civilization.

　　Now, new findings are greatly altering researchers´ notions about the time when corn revolution occurred. New dates for its emergence from Mesoamenrica do not support the widely held view. The evidence now suggests that the signs of corn in Americas can date back 5,500 years at least.

　　1. The first paragraph states that corn _____.

　　A. was mainly grown at sea level

　　B. was not grown below the elevation of 11,000 feet

　　C. was widely grown in Canada only

　　D. spread throughout Americas

　　2. The second paragraph implies that _____.

　　A. the purpose of Columbus´ exploration was to discover corn

　　B. corn was one of Columbus´ discoveries, but more precious than anything else

　　C. Columbus knew corn so well that he brought back to Europe at once

　　D. corn was the only Columbus´ discovery that was remembered

　　3. According to the passage, some varieties of corn can _____.

　　A. ripen little more than 2 months

　　B. last little more than 2 months

　　C. stay fresh for almost a year

　　D. stay alive from 2 months to almost a year

　　4. Corn helped the early communities to grow because _____.

　　A. it was easy to digest

　　B. it had a lot of varieties

　　C. it could produce high yields

　　D. it could last long

　　5. The widely held view was challenged by _____.

　　A. a new revolution

　　B. new findings about corn

　　C. the signs of corn 5,500 years ago

　　D. new dates for communities´ emergence

　　Women on a touring holiday of Britain were injured by an explosion in their motor van in the center of Norwich yesterday.

　　Shoppers, traders and businessmen in Red Lion Street were shocked by a loud bang, and seconds later the two men jumped over from the vehicle. Several people rushed to give assistance and helped to put out the fire inside the vehicle.

　　“I heard this explosion. It was pretty loud. I thought it could have been a bomb.” Said Mr. Leslie Webster, manager of the market, who was working in his office in Red Lion Street. “I looked out of the window and saw this lad leap from the van and roll on the ground. Then another lad came out of the van. He seemed to be in a worse state --- parts of his trousers were hanging below his knee.”

　　“I came downstairs to get a fire extinguisher(滅火器)， but by the time I got outside someone from the bank was in the van with an extinguisher.”

　　Mr. Webster, who lives at 71, Trinity Street, Norwich, said both victims were shocked. One was taken into the market´s office to await an ambulance. “The second man insisted on going back into the van to see if everything was all right, and five minutes later he came out with a drawer that was blazing.” He added.

　　The explosion was also heard inside the bank. Staff provided a fire extinguisher and telephoned for an ambulance.

　　Although a plastic window was blown out, damage inside the vehicle was mainly superficial.

　　The two men have spent the last six months touring the Continent and has traveled to Norwich from Snetterton. At the time of the incident their wives were shopping in the city.

　　6. The two men in the van ______.

　　A. were unhurt

　　B. were slightly hurt

　　C. were shocked and badly hurt

　　D. needed a long-time treatment

　　7. The word “l(fā)eap” most probably means ______.

　　A. jump over

　　B. step up

　　C. fall down

　　D. get out

　　8. In Mr. Webster´s opinion, the explosion ______.

　　A. was almost a bomb

　　B. wasn´t a bomb

　　C. was like a bomb

　　D. was a bomb

　　9. In the accident ______.

　　A. the windows of the bank were blown out

　　B. the contents of the van were damaged

　　C. everything in the van was all right

　　D. the van was burned

　　10. Which of the following is NOT true according to the passage?

　　A. Mr. Webster saw what had happened.

　　B. Mr. Webster helped to put out the fire.

　　C. Mr. Webster didn´t take a fire extinguisher to the van.

　　D. Mr. Webster wanted to help in the accident but he didn´t have a chance

　　參考答案：1--10 D B A C B， B AC D B