C

　　Lying in the sun on a rock, the cougar(美洲狮)saw Jeb and his son, Tom, before they saw it. Jeb put his bag down quickly and pulled his jacket open with both hands, making himself look big to the cougar. It worked. The cougar hesitated, ready to attack Jeb, but ready to forget the whole thing, too.

　　Jeb took off his jacket, grasped Tom and held him across his body, making a cross. Now the cougar's enemy looked even bigger, and it rose up, ready to move away, but unfortunately Tom got scared and struggled free of Jeb.

　　"Tom, No!" shouted his father.

　　But Tom broke and ran and that's the last thing you do with a cougar. The second Tom broke free, Jeb threw himself on the cougar, just as it jumped from the rock. They hit each other in mid?air and both fell. The cougar was on Jeb in a flash, forgetting about Tom, which was what Jeb wanted. Cougars are not as big as most people think and a determined man stands a chance, even with just his fists. As the cougar's claws got into his left shoulder, Jeb swung his fist at its eyes and hit hard. The animal howled（吼叫）and put its head back. Jeb followed up with his other fist. Then out o(本 文来 源于 贵_大-在线 htTP://WWw.GZu521.NEt]f the corner of his eye, Jeb saw Tom. The boy was running back to help his father.

　　"Knife, Tom," shouted Jeb.

　　The boy ran to his father's bag, while Jeb started shouting as well as hitting, to keep the cougar's attention away from Tom. Tom got the knife and ran over to Jeb. The cougar was moving its head in and out, trying to find a way through the wall. Jeb was making out of his arms. Tom swung with the knife, into the cougar's back. It howled horribly and ran off into the mountains.

　　44. Why did Jeb pull his jacket open when he saw the cougar?

　　A. To get ready to fight . B. To frighten it away.

　　C. To protect the boy. D. To cool down.

　　45. What do we know about cougars?

　　A. They are afraid of noises. B. They hesitate before they hit.

　　C. They are bigger than we think. D. They like to attack running people.

　　46. How did Jeb try to hold the cougar's attention?

　　A. By keeping shouting and hitting.

　　B. By making a wall out of his arms.

　　C. By throwing himself on the cougar.

　　D. By swinging his fists at the cougar's eyes.

　　47. Which of the following happened first?

　　A. The cougar jumped from the rock. B. Tom struggled free of his father.

　　C. Jeb asked Tom to get the knife. D. Jeb held Tom across his body.

　　D

　　Yellowstone Weather

　　Yellowstone National Park is at high altitude(海拔). Most of the park is above 7,500 feet (2,275 meters).

　　Yellowstone's weather is unpredictable. In summer, it may be warm and sunny with temperatures in the high 70s. At night in any given month, the temperature may drop close to freezing. So it is best to come prepared for cold evenings and mornings, especially if you are camping or hiking. When you leave your campsite, please leave it prepared for possible thundershowers and wind.

　　A sunny warm day may become fiercely stormy with wind, rain, sleet and sometimes snow. Without enough clothing, an easy hike or boat trip can turn into a battle for survival.

　　Seasonal Weather InformationSpring

　　Cold and snow continue into May, although temperatures gradually climb.Early in spring, daytime temperatures average in the 40s to 50s; by late May and June, they may reach the 60s and 70s. Nighttime lows fall below freezing.

　　Summer

　　Daytime temperatures are usually in the 70s, occasionally reaching the 80s in the lower elevations (高度). Nights are cool, temperatures may drop in the 40s and 30s-sometimes even the 20s. June can be cool and rainy; July and August tend to be somewhat drier, although afternoon thundershowers are common.Fall

　　Weather can be pleasant, although temperatures average 10-20 degrees lower than summer readings. Nighttime lows can fall into the teens and lower. Snowstorms increase in frequency as the weeks go by or towards the end of the fall season.Winter

　　Temperatures often stay near zero throughout the day, occasionally reaching high in the 20s. Suhzero nighttime lows are common. Annual snowfall averages nearly 150 inches in most of the park. At higher places, 200-400 inches of snow have been recorded.48. The author writes this passage most probably for those who plan to in Yellowstone National Park.

　　A. do research work B. take a business trip

　　C. have sports games D. spend their holidays or take a tour

　　49. Which of the following best describes Yellowston's weather?

　　A. Yellowstone's weather is generally changeable and it snows most of the year.

　　B. It's neither too hot in summer nor too cold in winter.

　　C. Weather in fall is pleasant and temperatures never fall below freezing.

　　D. It's pretty warm in the day and very cool at night throughout the year.

　　50. If you are planning to spend your holidays in Yellowstone National Park in summer, what should you take with you?

　　A.Just some light clothing such as T shirts or skirts.

　　B. Just some warm clothing such as sweaters and coats.

　　C. Both light clothing and warm clothing.

　　D. Either light clothing or warm clothing.

　　51. What does the underlined word "readings" refer to?"_____"

　　A.literary works B. books

　　C. announcements D. figures