Through a series of experiments an American scientist has gained an understanding of the social structure of the most complex of ant societies. The ants examined are the only creatures other than man to have given up hunting and collecting for a completely agricultural way of life. In their underground nests they plant gardens on soils made from finely cut leaves. This is a complex operation requiring considerable division of labor. The workers of this type of ant can be divided into four groups according to size. Each of the groups performs a particular set of jobs.   

The making and care of the gardens and the nursing of the young ants are done by the smallest workers. Slightly larger workers are responsible for cutting leaves to make them suitable for use in the gardens and for cleaning the nest. A third group of still larger ants do the construction work and collect fresh leaves from outside the nest. The largest are soldier ants, responsible for defending the nest.

To find out how good the various size - groups are at different tasks, the scientist measured the amount of work done by the ants against the amount of energy they used. He examined first the gathering and carrying of leaves. He selected one of the size groups, and then measured how efficiently these ants could find leaves and run back to the nest. Then he repeated the experiment for each of the other size groups. In this way he could see whether any group could do the job more efficiently than the group normally undertaking it. 

The intermediate-sized (中等的) ants that normally perform this task proved to be the most efficient for their energy costs, but when the scientist examined the whole set of jobs performed by each group of ants, it appeared that some sizes of worker ants were not suited to the particular jobs they performed .

1．According to the passage, the ants______.

A．grow something in their nests             B．go hunting for a living

C．cut leaves to make a fire                  D．do each of the jobs all together

2．It is observed that slightly larger ants perform more of the______.

      A．construction tasks                      B．defensive work

      C．household tasks                         D．dangerous work

3．The underlined word "good" means ______.

      A．co-operating       B．efficient            C．hardworking      D．responsible

4．The experiments made by the scientist were based on ______.

      A．special methods                         B．scientific theories

       C．personal interests                    D．systematic observations

Through several provinces _____ the longest river in China.

    A．walk      B．walks         C．run            D．runs

Lightning flashed through the darkness over Sibson’s bedroom skylight（天窗）.Sibson was shaken by a clap of thunder ____21___ he knew what was happening. The storm had moved directly _____22____ his two-story wooden house. Then he heard the smoke alarm beeping.
Sibson rushed down the stairs barefoot to     23     ; he opened the door to the basement（地下室）, and flames      24     out. Sibson ran back upstairs to call 911 from his bedroom. “I felt      25      because the room had a separate outdoor stairway,” he explains.
But the phone didn’t work, and when he tried to go down the outdoor stairway, he was      26     by a wall of flames. Sibson realized he was trapped（困住）.
Sibson’s house was three kilometers      27     the main road and was so well hidden by trees that he knew calling for help would be     28     .
Up a hill nearby lived Sibson’s neighbor, Huggons. He was lying in bed when something like a smoke alarm      29     his ears. He jumped out of bed, took his     30     and flashlight, and headed down the hillside toward the    31    . That was when he saw the rolling heavy smoke.
Huggons dialed 911, and the operator warned him not to    32   the house. But Huggons said, “There is no way I am going to listen to Sibson    33    and die in that fire.”
“Anyone there?” Huggons called out. Then he heard “Help! I’m trapped!” coming from the second floor balcony（阳台）. He entered the house, but soon had to run back to catch his     34    .
After one more    35   inside the house, Huggons gave up and     36   around back.
The wind parted the smoke just     37    for him to catch sight of Sibson. But there was no way to get to him. He    38   the flashlight into the woods and noticed a ladder. He took it over to the balcony and     39    Sibson down just as the second floor of the house fell off.
Sibson is still     40    when he tells the story. “ I was alone that night,” he says. “Then I heard the most beautiful sound in my life. It was Huggons.”

Lightning flashed through the darkness over Donald Lubeck’s bedroom skylight. The 80-year-old retired worker was shaken by a blast of thunder. It was 11 p.m. The storm had moved directly over his two-story wood home in the rural town of Belchertown, Massachusetts. Then he heard the smoke alarm beeping. Lubeck padded down the stairs barefoot and opened the door to the basement, and flames exploded out.
Lubeck fled back upstairs to call 911 from his bedroom, but the phone didn’t work. Lubeck realized he was trapped. “I started panicking,” he says.
His daughter and young granddaughters, who lived with him, were away for the night. No one will even know I’m home, he thought. His house was three miles off the main road and so well hidden by pines that Lubeck knew calling for help would be fruitless.
Up a hill about a third of a mile away lived Lubeck’s closest neighbors, Jeremie Wentworth and his wife. Wentworth had been lying down, listening to the radio when it occurred to him that the sound was more like a smoke detector. He jumped out of bed, grabbed a cordless phone and a flashlight, and headed down the hillside toward the noise.
He dialed 911. “Is anyone there?” he called out as he approached the house. Wentworth knew that Lubeck lived in the house.
Then he heard, “Help me! I’m trapped!” coming from the balcony off Lubeck’s bedroom.
“I ran in and yelled,‘Don, where are you?’ Then I had to run outside to catch my breath.”
After one more attempt inside the house, he gave up and circled around back. But there was no way to get to him. “I shined the flashlight into the woods next to an old shed and noticed a ladder,” says Wentworth. He dragged it over to the balcony and pulled Lubeck down just as the second floor of the house collapsed.
Wentworth and Lubeck don’t run into each other regularly, but Lubeck now knows that if he ever needs help, Wentworth will be there.
Lubeck still chokes up when he tells the story. “I was alone,” he says. “Then I heard the most beautiful sound in my life. It was Jeremie.”
【小题1】According to the text, Lubeck___________.

Lightning flashed through the darkness over Donald Lubeck’s bedroom skylight. The 80-year-old retired worker was shaken by a blast of thunder. It was 11 p.m. The storm had moved directly over his two-story wood home in the rural town of Belchertown, Massachusetts. Then he heard the smoke alarm beeping. Lubeck padded down the stairs barefoot and opened the door to the basement, and flames exploded out.

Lubeck fled back upstairs to call 911 from his bedroom, but the phone didn’t work. Lubeck realized he was trapped. “I started panicking,” he says.

His daughter and young granddaughters, who lived with him, were away for the night. No one will even know I’m home, he thought. His house was three miles off the main road and so well hidden by pines that Lubeck knew calling for help would be fruitless.

Up a hill about a third of a mile away lived Lubeck’s closest neighbors, Jeremie Wentworth and his wife. Wentworth had been lying down, listening to the radio when it occurred to him that the sound was more like a smoke detector. He jumped out of bed, grabbed a cordless phone and a flashlight, and headed down the hillside toward the noise.

He dialed 911. “Is anyone there?” he called out as he approached the house. Wentworth knew that Lubeck lived in the house.

Then he heard, “Help me! I’m trapped!” coming from the balcony off Lubeck’s bedroom.

“I ran in and yelled,‘Don, where are you?’ Then I had to run outside to catch my breath.”

After one more attempt inside the house, he gave up and circled around back. But there was no way to get to him. “I shined the flashlight into the woods next to an old shed and noticed a ladder,” says Wentworth. He dragged it over to the balcony and pulled Lubeck down just as the second floor of the house collapsed.

Wentworth and Lubeck don’t run into each other regularly, but Lubeck now knows that if he ever needs help, Wentworth will be there.

Lubeck still chokes up when he tells the story. “I was alone,” he says. “Then I heard the most beautiful sound in my life. It was Jeremie.”

1.According to the text, Lubeck___________.

A．stayed calm in the fire                    B．couldn’t find a safe way out

C．lived on the first floor                    D．called for help in the fire

2.How did Wentworth help Lubeck escape?

A．He called 911.

B．He went upstairs and took Lubeck out.

C．He put out the fire.

D．He used a ladder and pulled Lubeck down.

3.Which of the following factors was not mentioned in the text that almost cost Lubeck’s life?

A．He was living in his wood home alone that night.

B．The storm was too heavy and the fire was too fierce.

C．He lived far from the main road and was surrounded by pines.

D．He was too frightened to escape from the danger.

4.What does the text mainly talk about?

A．A near neighbour is better than a distant cousin.

B．A good way to get a narrow escape.

C．God helps those who help themselves.

D．Blood is thicker than water.