[单项选择]

The Earth has a force that pulls thing toward itself. We call this force gravity. This is something we live with all the time, and we take it for granted and hardly ever think about it . But it is a most important factor in rocket operation and must 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 forever and never come down. The speed at which it would have to be thrown 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 space
A. accept it without questioning it
B. never notice its presence
C. hardly think about how to use it
D. often try to escape from it

[单项选择]

The Earth has a force that pulls thing toward itself. We call this force gravity. This is something we live with all the time, and we take it for granted and hardly ever think about it . But it is a most important factor in rocket operation and must 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 forever and never come down. The speed at which it would have to be thrown 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 space
A. runs along the hillside
B. does not need any further power
C. runs freely to all directions
D. does not meet with air resistance

[单项选择]What is the first thing Tim Berners-Lee has to do before establishing the smarter Web
A. To set up standards for all Internet users.
B. To add descriptive tags or "metadata".
C. To find the proper methods for the Web.
D. To relate to metadata from various Web sites.

[单项选择]Obviously he has done a very terrible thing today, but ______ , he can't be held responsilSle in the criminal justice system.
A. justifiably
B. legally
C. reasonably
D. understandingly

[单项选择]As the lecturer has said, talent is one thing, while its ______ expression is another.
A. turbulent
B. tremendous
C. triumphant
D. tentative

[单项选择]By the treaty each country {{U}}pledged{{/U}} itself to assist the other in case of war.
A. assured
B. applied
C. obliged
D. promised

[单项选择]When one thing in motion hits another thing, it ______ with it.
A. coincides
B. collides
C. reconciles
D. converges

[单项选择]

Motivation is the driving force within individuals that impels them to action.（）

A. impedes
B. interferes
C. holds
D. pushes

[单项选择]What is the character of British labor force


A. homogeneous
B. creative
C. imaginary
D. hard working

[单项选择]The Coriolis force causes all moving projectiles on Earth to {{U}}be deflected{{/U}} from a straight line.
A. spring
B. deviate
C. be retracted
D. be conceived