Seen from space the Earth is covered in a blue mantle. It is a planet on which the continents are dwarfed(相形见绌)by the oceans surrounding them and the vastness of the marine area.

An astonishing 80 percent of all the life on Earth is to be found hidden beneath the waves and this vast global ocean pulses around our world driving the natural forces which keep life on our planet.

The oceans provide necessary sources of protein, energy, minerals and other products of use the world over and the rolling of the sea across the planet creates over half our oxygen, drives weather systems and natural flows of energy and nutrients around the world, transports water masses many times greater than all the rivers on land combined and keeps the Earth habitable.

Without the global ocean there would be no life on Earth.

It is seriously worrying, then, that we are damaging the oceans on a scale that is unimaginable to most people.

We now know that human activity can have serious influences on the vital forces governing our planet. We have fundamentally changed our global climate and are just beginning to understand the consequences of that. As yet largely unseen，but just as serious，are the influences we are having on the oceans. A healthy ocean has diverse ecosystems and strong and healthy habitats. The actual state of our oceans is a far cry from this natural level.

A large quantity of human pressures are being exerted both directly and indirectly on ocean ecosystems the world over. Consequently ecosystems are collapsing as marine species are driven towards extinction and ocean habitats are destroyed. With the decrease and removement of their diversity, ocean ecosystems are losing their natural recovery.

20．The 2nd and the 3rd paragraphs are given mainly to describe________．

A．what the oceans look like

B．what the oceans are made up of

C．what lives in the oceans

D．what functions the oceans have

21．The oceans provide all the following except ________．

A. various marine creatures

B. rich living resources

C. all natural forces

D. comfortable habitats for man

22．Man has not yet realized that ________．

A．he has done harm to the oceans

B．he has done harm to the planet

C．he has benefited from the oceans

D．he has benefited from the planet

23．The best title for this passage should be ________．

A. Protecting our planet

B. Defending our oceans

C. Making good use of our oceans

D. A glimpse of the oceans

Seen from space the Earth is covered in a blue mantle. It is a planet on which the «

continents are dwarfed (相形见绌）by the oceans surrounding them and the vastness of the marine area.

An astonishing 80 percent of all the life on Earth is to be found hidden beneath the waves and this vast global ocean pulses around our world driving the natural forces which keep life on our planet.

The oceans provide necessary sources of protein, energy, minerals and other products of use the world over and the rolling of the sea across the planet creates over half our oxygen, drives weather systems and natural flows of energy and nutrients around the world, transports water masses many times greater than all the rivers on land combined and keeps the Earth habitable.

Without the global ocean there would be no life on Earth.

It is seriously worrying, then, that we are damaging the oceans on a scale that is unimagnalbe  to most people.

We now know that human activity can have serious influences on the vital forces working - on our planet. We have fundamentally changed our global climate and are just beginning to understand the consequences of that .As yet largely unseen，but just as serious，are the influences we are having on ihe oceans. A healthy ocean has diverse ecosystems and strong and healthy habitats. the actual state of our oceans is a far cry from this natural level.

A large quantity of human pressures are being exerted both directly and indirectly on ocean ecosystems the world over. Consequently ecosystems are collapsing as marine speciesare driven towards extinction and ocean habitats are destroyed. With the decrease and removement of their diversity , ocean ecosystems are losing their natural recovery.

59.  The 2nd and the 3rd paragraphs are given mainly to describe  ______.

A. what the oceans look like                         B. what the oceans are made up of

C. what live in the oceans                             D. what functions the oceans have

60.  The oceans provide all the following except ______

A. various marine creatures                          B. rich living resources

C. all natural forces                                     D. comfortable habitats for man

61.  Man has not yet realized ______

A. that he has done harm to the oceans B. that he has done harm to the planet C. that he has benefited from the oceans D. that he has benefited from the planet

62.  The best title for this passage should be ______

A. Protecting our planet                                B. Defending our oceans

C. Making good use of our oceans                D. A glimpse of the oceans

Redwood trees are the tallest plants on the earth，reaching heights of up to 100 meters．They are also known for their longevity，typically 500 to 1000 years，but sometimes more than 2000 years．A hundred million years ago，in the age of dinosaurs，redwoods were common in the forests of a much more moist and tropical North America．As the climate became drier and colder，they declined to a narrow strip along the Pacific coast of Northern Califomia．

The trunk of redwood trees is very strong and usually forms a single straight column．It is covered with a soft bark．This bark can be pretty thick，well over two feet in the more mature trees．It gives the older trees a certain kind of protection from insects，but the main benefit is that it keeps the center of the tree harmless from moderate forest fires because of its thickness．This fire resistant quality explains why the giant redwood grows to live that long．While most other types of trees are destroyed by forest fires，the giant redwood actually prospers because of them．

Moderate fires will clear the ground of competing plant life，and the rising heat dries and opens the ripe fruit of the redwood，releasing many thousands of seeds onto the ground below．

??? New trees are often produced from shoots，little baby trees，which form at the base of the trunk．These shoots grow slowly，fed by the root system of the “mother’’ tree．When the main tree dies，the shoots are then free to grow as full trees，forming a “fairy ring” of trees around the original tree．These trees，in turn，may give rise to more shoots，and the cycle continues．

1.Why were redwood trees easier to find in the forests of North America millions of years ago?

A．The trees were taller and stronger．

B．The soil was softer for seeds to develop．

C．The climate there was warmer and wetter．

D．The temperature was lower along the Pacific coast．

2.Which of the following is a function of the tree bark as mentioned in the passage?

A．It allows redwood trees to bear seeds．

B．It prevents redwood trees from attack by insects．

C．It helps redwood trees absorb water in the air．

D．It makes redwood trees more beautiful and appealing．

3.Why do redwood trees grow to live that long according to the passage?

A．They have heavy and straight tree trunks．

B．They are properly watered and catered to．

C．They are more resistant to fire damage than other trees．

D．They produce many young trees to maintain their life cycle．

4.How does a “fairy ring’’ form according to the passage?

A．By killing an old tree．????????????? ????????????? ????????????? ????????????? B．By connecting root systems．

C．By inserting holes into old trees．????????????? ????????????? D．By surrounding a mature tree．

The world is not hungry, but it is thirsty. It seems strange that nearly 3/4 of the earth is covered with water while we say we are short of water. Why? Because about 97% of water on the earth is sea water which we can’t drink or use for watering plants directly. Man can only drink and use the 3% the water that comes from rivers and lakes. And we can’t even use all of that, because some of it has been polluted.
Now more water is needed. The problem is: can we avoid a serious water shortage later on? First, we should all learn how to save water. Secondly, we should find out the ways to reuse it. Scientists have always been making study in this field. Today, in most large cities water is used only once and then runs to the sea or rivers. But it can be used again. Even if every large city reused its water, still there would not be enough. What could people turn to next?
The sea seems to have the best answer. There is a lot of water in the sea. All that needs to be done is to get the salt out of the sea water. This is expensive, but it’s already in use in many parts of the world. Scientists are trying to find a cheaper way of doing it. So you see, if we can find a way out, we’ll be in no danger of drying up.
【小题1】The world is thirsty because ___________.

The world is not hungry, but it is thirsty. It seems strange that nearly 3/4 of the earth is covered with water while we say we are short of water. Why? Because about 97% of water on the earth is sea water which we can’t drink or use for watering plants directly. Man can only drink and use the 3% the water that comes from rivers and lakes. And we can’t even use all of that, because some of it has been polluted.

Now more water is needed. The problem is: can we avoid a serious water shortage later on? First, we should all learn how to save water. Secondly, we should find out the ways to reuse it. Scientists have always been making study in this field. Today, in most large cities water is used only once and then runs to the sea or rivers. But it can be used again. Even if every large city reused its water, still there would not be enough. What could people turn to next?

The sea seems to have the best answer. There is a lot of water in the sea. All that needs to be done is to get the salt out of the sea water. This is expensive, but it’s already in use in many parts of the world. Scientists are trying to find a cheaper way of doing it. So you see, if we can find a way out, we’ll be in no danger of drying up.

1.The world is thirsty because ___________.

2.Which of the following is TRUE?

3.From the passage we learn that __________.