[单项选择]Do you realize that every time you take a step, the bones in you hip are subjected to forces between four and five times your body weight ^①When you are running, this force is increased further still. What happens if through disease a hip-joint ceases to be able to resist such forces For many years hip-joints and other body joints have been replaceable either partially or completely. It is after all a simple ball and socket joint; it has certain loads imposed on it; it needs reliability over a defined life; it must contain materials suitable for the working environment. Any engineer will recognize these as characteristic of a typical engineering problem, which doctors and engineers have worked together to solve, in order to bring a fresh Jease of life to people who would otherwise be disabled, ^②
This typifies the way in which engineers work to help people and create a better quality of life. The fact that this country has the most efficient agricultural indust
A. When one is walking.
B. When one is running.
C. When one is standing.
D. When one is lying down.

[单项选择]Do you realize that every time you take a step, the bones in you hip are subjected to forces between four and five times your body weight ^①When you are running, this force is increased further still. What happens if through disease a hip-joint ceases to be able to resist such forces For many years hip-joints and other body joints have been replaceable either partially or completely. It is after all a simple ball and socket joint; it has certain loads imposed on it; it needs reliability over a defined life; it must contain materials suitable for the working environment. Any engineer will recognize these as characteristic of a typical engineering problem, which doctors and engineers have worked together to solve, in order to bring a fresh Jease of life to people who would otherwise be disabled, ^②
This typifies the way in which engineers work to help people and create a better quality of life. The fact that this country has the most efficient agricultural indust
A. mechanical engineers
B. doctors and engineers
C. biologists, doctors and farmers
D. farmers, biologists and engineers

[单项选择]—Could you do me a favor and take the box up to the sixth floor
—__________.
A. With pleasure
B. My pleasure
C. No wonder
D. No comment

[单项选择]
Do you know that we live a lot longer now than the people who were born before us One hundred years ago the average woman lived to be 45. But now, she can live until at least 80.
One of the main reasons for people living longer is that we know how to look after ourselves better. We know which foods are good for us and what we have to eat to make sure our bodies get all the healthy things they need. We know why we sometimes get ill and what to do to get better again. And we know how important it is to do lots of exercise to keep our hearts beating healthily.
But in order that we don’t slip back into bad habits, let’s have a look at what life was like 100 years ago.
Families had between 15 and 20 children, although many babies didn’t live logn. Children suffered from lots of diseases, especially rickets (佝偻病) and scurvy (坏血病), which are both caused by bad diets. This is because many families were very poor a
A. Right
B. Wrong
C. Not mentioned

[单项选择]

What do you do with your empty cans and bottles There are two choices, throwing them away or recycling them. Throwing away a metal beverage (饮料) container wastes as much energy as filling a can with gasoline and pouring half out. Besides wasting energy, throwing away bottles and cans causes pollution, increases the volume of solid waste, and uses up natural resources. To control these problems, only nine states have adopted bottle laws. The United States government should require every state to have a bottle law or impose (制定) a national bottle law.
To understand how a bottle law can help, you must know how it works. When consumers buy canned or bottled beverages at a store, they pay deposits. This deposit can range from twenty to fifty cents per bottle or can. In order to get this deposit back, the bottles and cans must be returned to supermarkets after they are emptied. The supermarkets then return the bottles and cans to their manufacturers for either reusing or recycl
A. the nine states support it
B. the consumers pay deposits
C. the manufacturers recycle the empty containers
D. the consumers, supermarkets and manufacturers make a joint effort