阅读理解：

　　The Earth has a force that pulls things toward itself. We call this force gravity（引力）. This is something we love with all the time, and hardly ever think about it. But it is a most important factor（因素）in rocket（火箭）operation and must be overcome if we are to get anywhere in space, or off the ground at all.

　　Take the throwing of a ball as an example. The harder the ball is thrown, the faster and higher it will go. What is the secret? Its speed. If we could throw the ball hard enough it would go up and up and up forever and never come down. The speed at which it would have to be thrown to do this is known as escape speed. Of course, we cannot throw a ball hard enough because the speed required to escape completely from the Earth’s gravity is seven miles per second, or over twenty-five thousand miles per hour.

　　Once escape speed has been reached by a spaceship, no further power is needed. A rocket aimed at the Moon, for instance, will “:coast”（滑行）the rest of the way because the Earth’s gravity cannot then pull it back, and there is no air resistance in space to slow it down. This “coasting” is known as “free fall”. That does not mean the rocket is falling down towards the Earth but that it is travelling freely in space without the help of power, like a bicycle coasting downhill.

　　Free fall is an important feature of space travel: it would be impossible to carry enough oil to supply powered flight all the time.

1．What is the most important factor for a rocket to escape from the Earth?　　

　[　　]

A．To travel as fast as it can.

B．To overcome the Earth’s gravity.

C．To get away from the air resistance.

D．To have strong power in its operation.

2．How fast will a rocket escape completely from the Earth’s gravity?

　[　　]

A．Seventy miles per second.

B．Seven thousand miles per hour.

C．Twenty-five thousand miles per second.

D．Twenty-five thousand miles per hour.

3．As there is always the Earth’s gravitational pull, people ______.

[　　]

A．accept it without questioning it

B．never feel interested in its presence

C．hardly think about how to use it

D．often try to escape from it

4．When a bicycle “coasts” downhill, it ______.

　　　[　　]

A．runs along the hillside

B．does not need any further power

C．runs freely in all directions

D．does not meet with air resistance

5．It’s unnecessary to supply power for the flight in space all the time, because ______.

　　　[　　]

A．few spaceships complete their flight operations

B．the Earth’s gravity cannot be overcome

C．no further power is needed after the escape speed is reached

D．“free fall” takes the place of the Earth’s gravity

What Is Natural Medicine

Natural Medicine is to use the natural environment, the nature of the material itself to cure diseases and restore the health. It involves bettering one’s breathing way, sunbathing, improving one’s diets and so on, which play an important part in our healthcare.

Start a Rewarding Career Today

The Australian Institute of Applied Sciences College of Natural Medicine provides you with Nationally Recognized natural medicine courses that can be studied in the comfort of your own home, or at our Brisbane campus in the heart of Stones Corner. AIAS College of Natural Medicine has been providing accredited (官方认可的) natural health courses for more than 20 years, and offers accredited certificate, diploma and advanced diploma level natural medicine, beauty and massage (按摩) courses.

Why Study at the Australian Institute of Applied Sciences

With over 36 years of specialized training and 120 courses, our Natural Medicine College is Australia’s longest running and most sought after training provider for Natural Medicine Education. Our state of the art facilities, highly experienced instructors and friendly support staff make us the first choice for Distance Education and On-campus study.

Studying at Home

All of our courses are available to study at home. We provide all the material and support you will need to successfully complete your course.

Benefits of Studying at Home

●Work at your own pace.

●No need to travel or relocate closer to a campus.

●No interruption to your existing commitments.

●You are still in full contact with the college via Telephone, Email and Post, so you won’t be out of touch with the latest training techniques.

60. You can learn how to ______ at the Australian Institute of Applied Sciences College of Natural

Medicine.

A. apply science to our life                        B. operate on various patients

C. adjust one’s diet or breath                      D. look after mentally-ill people

61. One of the reasons for your choice of going to the college is that _______.

A. it is the oldest college of this type in Australia

B. it offers more courses than any other college

C. you may find the best art facilities there

D. you will get accredited certificate or diploma

62. If you take the courses at home, you are more likely to _______.

A. focus on your own interests              B. adjust your study schedules

C. get any help from instructors            D. keep up with new techniques

 

What Is Natural Medicine

Natural Medicine is to use the natural environment, the nature of the material itself to cure diseases and restore the health. It involves bettering one’s breathing way, sunbathing, improving one’s diets and so on, which play an important part in our healthcare.

Start a Rewarding Career Today

The Australian Institute of Applied Sciences College of Natural Medicine provides you with Nationally Recognized natural medicine courses that can be studied in the comfort of your own home, or at our Brisbane campus in the heart of Stones Corner. AIAS College of Natural Medicine has been providing accredited (官方认可的) natural health courses for more than 20 years, and offers accredited certificate, diploma and advanced diploma level natural medicine, beauty and massage (按摩) courses.

Why Study at the Australian Institute of Applied Sciences

With over 36 years of specialized training and 120 courses, our Natural Medicine College is Australia’s longest running and most sought after training provider for Natural Medicine Education. Our state of the art facilities, highly experienced instructors and friendly support staff make us the first choice for Distance Education and On-campus study.

Studying at Home

All of our courses are available to study at home. We provide all the material and support you will need to successfully complete your course.

Benefits of Studying at Home

●Work at your own pace.

●No need to travel or relocate closer to a campus.

●No interruption to your existing commitments.

●You are still in full contact with the college via Telephone, Email and Post, so you won’t be out of touch with the latest training techniques.

60. You can learn how to ______ at the Australian Institute of Applied Sciences College of Natural

Medicine.

A. apply science to our life                         B. operate on various patients

C. adjust one’s diet or breath                      D. look after mentally-ill people

61. One of the reasons for your choice of going to the college is that _______.

A. it is the oldest college of this type in Australia

B. it offers more courses than any other college

C. you may find the best art facilities there

D. you will get accredited certificate or diploma

62. If you take the courses at home, you are more likely to _______.

A. focus on your own interests               B. adjust your study schedules

C. get any help from instructors             D. keep up with new techniques

What Is Natural Medicine

Natural Medicine is to use the natural environment, the nature of the material itself to cure diseases and restore the health. It involves bettering one’s breathing way, sunbathing, improving one’s diets and so on, which play an important part in our healthcare.

Start a Rewarding Career Today

The Australian Institute of Applied Sciences College of Natural Medicine provides you with Nationally Recognized natural medicine courses that can be studied in the comfort of your own home, or at our Brisbane campus in the heart of Stones Corner. AIAS College of Natural Medicine has been providing accredited (官方认可的) natural health courses for more than 20 years, and offers accredited certificate, diploma and advanced diploma level natural medicine, beauty and massage (按摩) courses.

Why Study at the Australian Institute of Applied Sciences

With over 36 years of specialized training and 120 courses, our Natural Medicine College is Australia’s longest running and most sought after training provider for Natural Medicine Education. Our state of the art facilities, highly experienced instructors and friendly support staff make us the first choice for Distance Education and On-campus study.

Studying at Home

All of our courses are available to study at home. We provide all the material and support you will need to successfully complete your course.

Benefits of Studying at Home

●Work at your own pace.

●No need to travel or relocate closer to a campus.

●No interruption to your existing commitments.

●You are still in full contact with the college via Telephone, Email and Post, so you won’t be out of touch with the latest training techniques.

60. You can learn how to ______ at the Australian Institute of Applied Sciences College of Natural

Medicine.

A. apply science to our life                        B. operate on various patients

C. adjust one’s diet or breath                      D. look after mentally-ill people

61. One of the reasons for your choice of going to the college is that _______.

A. it is the oldest college of this type in Australia

B. it offers more courses than any other college

C. you may find the best art facilities there

D. you will get accredited certificate or diploma

62. If you take the courses at home, you are more likely to _______.

A. focus on your own interests               B. adjust your study schedules

C. get any help from instructors             D. keep up with new techniques

.

What Is Natural Medicine

Natural Medicine is to use the natural environment, the nature of the material itself to cure diseases and restore the health. It involves bettering one’s breathing way, sunbathing, improving one’s diets and so on, which play an important part in our healthcare.

Start a Rewarding Career Today

The Australian Institute of Applied Sciences College of Natural Medicine provides you with Nationally Recognized natural medicine courses that can be studied in the comfort of your own home, or at our Brisbane campus in the heart of Stones Corner. AIAS College of Natural Medicine has been providing accredited (官方认可的) natural health courses for more than 20 years, and offers accredited certificate, diploma and advanced diploma level natural medicine, beauty and massage (按摩) courses.

Why Study at the Australian Institute of Applied Sciences

With over 36 years of specialized training and 120 courses, our Natural Medicine College is Australia’s longest running and most sought after training provider for Natural Medicine Education. Our state of the art facilities, highly experienced instructors and friendly support staff make us the first choice for Distance Education and On-campus study.

Studying at Home

All of our courses are available to study at home. We provide all the material and support you will need to successfully complete your course.

Benefits of Studying at Home

●Work at your own pace.

●No need to travel or relocate closer to a campus.

●No interruption to your existing commitments.

●You are still in full contact with the college via Telephone, Email and Post, so you won’t be out of touch with the latest training techniques.

55. You can learn how to ______ at the Australian Institute of Applied Sciences College of Natural

Medicine.

A. apply science to our life                         B. operate on various patients

C. adjust one’s diet or breath                      D. look after mentally-ill people

56. One of the reasons for your choice of going to the college is that _______.

A. it is the oldest college of this type in Australia

B. it offers more courses than any other college

C. you may find the best art facilities there

D. you will get accredited certificate or diploma

57. If you take the courses at home, you are more likely to _______.

A. focus on your own interests                      B. adjust your study schedules

C. get any help from instructors                       D. keep up with new techniques