数列{an}中，a1=1，an+1=an+2n，则an=（ ） A．n2-n+1

One August afternoon, Richard Allen dropped off his last passenger, Mrs. Carey. Lifting two grocery bags, he followed her across the yard and stood on the step of her house. Glancing up, he saw a large wasp（黄蜂） nest under the roof. Allen had heard that wasps can become more likely to sting (sting, sting, stung蜇) in summer. He mentioned this to Mrs. Carey, who had opened the door.

“Oh, they don’t bother me,” she said lightly. “I go in and out all the time.”

Anxiously, Allen looked at the nest again—— to see the wasps flying straight at him. “Hurry!” he shouted to Mrs. Carey. “Get in!”

She stepped quickly inside. Allen ran for his mini-bus. Too late; they were upon him. Just as he jumped aboard, half a dozen red spots showed on his arm, and he felt more on his back and shoulders.

As he was driving down the road, Allen felt as if something was burning at the back of his neck, and the “fire” was spreading forward toward his face. And immediate anxiety took hold of him. Allen knew that stings could cause some persons to die. But he had been stung the previous summer and the after-effects soon passed. However, what he didn’t know what that the first sting had turned his body into a time bomb waiting for the next to set off an explosion.

Miles from the nearest medical assistance, Allen began to feel his tongue thick and heavy and his heartbeat louder. Most frightening, he felt his breathing more and more difficult. He reached for the radio mike（话筒）, trying to call the mini-bus center, but his words were hardly understandable. Signals were also poor that far out. He knew a rescue team was on 24-hour duty at the Amherst Fire Department’s north station. So his best chance was to make a run for it.

Rushing down the mountain, Allen tried not to panic, focusing his mind on each sharp turn. He was almost through the last of them when he felt sure he was going into shock（休克）. Just then he reached for the radio mike again.

“Call fire station,” he shouted, concentrating to form the words. “Emergency. Bee sting. Emergency. There in ten minutes.”

“Five-ten,” the center replied.

Hold on, Allen thought. Keep your eyes open. Breathe. Keep awake.

At last he reached the station. Two firemen ran out. Allen felt their hands grasp him before he hit the ground. You made it, he thought.

小题1:It is mentioned in the passage that wasps are more likely to attack when _______.

A．there are huge noises

B．strangers are approaching

C．the air is filled with food smell

D．the hottest season comes around小题2:Allen didn’t know that if stung by wasps again, he would _______.

A．have no after-effects

B．suffer from sharper pain

C．surely lose his life

D．become more sensitive小题3:Allen failed at his first attempt to send his message to the mini-bus center because _______.

A．he was unable to speak clearly

B．his radio equipment was poor

C．he was in a state of shock

D．no one was on duty小题4:Which would be the best title for the passage?

A．Allen, A Helpless Driver

B．Wasps, Bloody Killers

C．A Race Against Death

D．War Against Wasps

灌装方法有（）和二次灌装法。

在脓疱病的早期，首选的物理治疗是

A．激光

B．热敷

C．紫外线

D．红外线

E．超短波

男孩最终身高高于女孩的主要原因是

A．男孩发育水平高于女孩

B．男孩发育比女孩晚，但发育时间长，幅度大

C．男孩体育运动量大

D．男孩瘦体重多，生长快

E．以上都不是

发电机可以与易燃易爆品和杂物混合堆放在一起，只要有离开一定的距离就行。