[填空题]When we are trying to change our diet, we usually will be anxious because we are nervous about ______.

[填空题]When we are trying to change our diet, we usually will be anxious because we are nervous about ______.

[填空题]It can be easier to change our diet a lot than to change it a little.

[单项选择]
The primary consideration in achieving a balanced diet is now how much or how little we eat, but what we eat. Basically we need carbohydrates, protein, fat, vitamins and minerals, together with regular but not excessive exercise.
Carbohydrates are found in foods such as bread, potatoes and sugar. They are excellent energy products, but if eaten to excess may be largely converted to fat and a reduction in the amount of carbohydrates or "starchy: foods is one of the obvious ways to reduce weight, since most of us eat too much of them anyway.
Protein, found in meat and cheese, is used for tissue building and in the developed countries most people eat about 110g daily, which is a good deal more than the recommended minimum of 70g a day. Animal fats, e. g. butter are also good sources of energy, but are sometimes held to caus increased cholesterol levels in the blood (which may lead to fatty deposits in the a
A. avoiding taking in animal fat.
B. reducing the amount of carbohydrates.
C. not taking in excessive vitamins.
D. taking in enough iron.

[单项选择]

When we see well, we do not think about our eyes very often. (76) It is only when we cannot See perfectly that we realize how important our eyes are.
People who are near-sighted can only see things that are very close to their eyes. Everything else seems blurry (unclear). Many people who do a lot of work, such as writing, reading and sewing, become near-sighted.
People who are far-sighted suffer from just the opposite problem. They can see things that are far away, but they have difficulty in reading a book unless they hold it at arm’s length, lf they want to do much reading, they must get glasses, too.
Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism (散光). This, too, can be corrected by glasses. Some people’s eyes become cloudy because of cataracts(白内障). Long ago these people often became blind. Now, however, it is possible to operate on the cataracts and remove them.
A. one eye bigger than the other
B. eyes that are not exactly the right shape
C. a difficulty that can be corrected by an operation
D. an eye difficulty that cannot be corrected by glasses