2012年上海市长宁区高三英语一模试卷 (1)(4)

Section C

Directions:Read the following text and choose the most suitable heading from A-F for each

paragraph. There is one extra heading which you do not need.

A . The different structure of blue holes.

B. Why scientists are interested in blue holes.

C. How a blue hole comes into being.

D. Blue holes exploring is becoming popular.

E. Rules to obey when diving into blue holes.

F. The general definition of a blue hole.

76._____________________

A blue hole is a flooded sea cave with a hole that opens up at the land's surface. These cave

systems form in carbonate rock, often on islands. Some blue holes have very special rock

formations and water chemistry. Far below sea level, they contain some of the harshest

environments on Earth, with no oxygen and no light. Yet these areas are filled with life forms that

have adapted to the extreme conditions.

77.___________________

Blue holes get their name from the color some have when seen from the air. The color is

usually a reflection of the sky on the water. Blue holes are the result of erosion in which water

breaks down rock. Rain falling thousands of years ago contained chemicals which slowly wore

away at the limestone landmass. These holes later filled with sea water as the sea level changed.

The rising and falling of sea levels and the mixture of salt and fresh water further wore away at

these cave formations.

78.____________________________

These flooded cave systems can be found in the ocean, or they can be found inland. Ocean

caves are affected by tides, so they always have water movement. But blue holes on land are very

still. They have several layers of water, chemicals, and bacteria. The top layer of fresh water

comes from rainfall. This layer acts like a cap on top of the layered mixture, and keeps out oxygen

from the atmosphere. The fresh water floats on a denser layer of saltwater. Underneath this is a

layer of poisonous hydrogen sulfide, produced by bacteria living in the water. Underneath this

layer is anoxic seawater -- water that does not contain any oxygen.

79._______________________

Information gathered from these blue holes is helping scientists to increase their understanding of biology, archaeology and geology. But exploring these blue hole environments brings danger as well as discovery.Scientists are interested in these caves because oxygen-free conditions there are similar to those on Earth long ago, before oxygen existed on our planet.But there are many difficulties involved in diving into blue holes.

80._____________________

One reason blue holes have not been fully explored is that they can be extremely dangerous. There are many safety rules that divers must follow to help ensure their survival. First, divers must have training and experience to swim in these caves.Divers who explore a cave for the first time must establish a thin rope called a guideline. This line helps them to safely enter and exit the cave without getting lost.

Section D

Directions: Read the passage carefully. Then answer the questions or complete the statements in the no more than 10 words.

Squeezed into a small space with two other friends, I had a sense of pride to be able to be the mission commander of this space flight. I looked at my friends on each side and gave them a thumps-up we set out minds to bring our spacecraft to Mars.

Our objective was very important. It has been years since scientists began arguing about the possibility of existence of life on Mars. Many arguments arose, saying that the pictures of Mars, taken by various space explorations, had given them sufficient proof that only intelligent being could have made those structures. Others maintained that what looked like a face in the pictures was nothing more than a flash of lights and so the arguments continue without conclusion.

To prove this once and for all, an decision was made to launch an expedition(探险) into space. The truth about the possibility of life on Mars was about to be confirmed beyond any further doubt. Although no reports of an alien race was recorded, I could not help thinking about my reactions when I came to face to face with one of their kind. How would I greet them? What would I say? Would they be willing to understand the human race? I did not take to the thought of landing up on their lab tables, being the object of tests and explorations. How frightening a prospect!

My crew and I were the best among our group of trainees. We practiced hard together, training hand in hand, filled with a single aim, which is to fly safely to Mars and back. This feeling was tense and everyone was highly excited, as the day drew nearer. We were anxious to see what Mars was like but the uncertainty held us with fear. The training increased in intensity (强度) as everyone raced against time and practiced as much as possible.

The moment came and by in a flash. The countdown proceeded, the life-off was tense and soon we were deep in space, floating about freely and went about preparing the spaceship for the intended landing. Since the trip was scheduled to take about three years to arrive at Mars, we slept in a special room to prevent us from aging. So I drifted off to sleep peacefully and suddenly I felt some woke me up. We must have arrived at Mars and my crew was trying to wake me up.

I opened my eyes slowly and saw a familiar face. “Why would my English teacher wake me up?” I thought. Oh, no. Instead of medals and praise that I Should receive, all I had was a severe warning against sleeping in class and spent the rest of the lesson standing in a corner.

( Note:Answer the questions or complete the statements in No More Than 10 Words.)

81.The author giving a thumbs-up showed that ____________.