12.It took us over an hour_______along the street.

It took us over an hour 　　　　　　　along the street.

12.It took us over an hour_______along the street.

Alzheimer’s disease is a major national health problem. Nearly 2 million Americans over the age of 65 have Alzheimer’s disease. It is a leading cause of death among the elderly. But Alzheimer’s disease is not confined （限于） to the aged. There may be a million or more people under the age of 65 suffering from the disease.
　　At one time, people suffering from the disease were said to be“getting old”.The disease was thought to be a natural part of growing old, but it is now known that Alzheimer’s disease strikes young and old alike. It is an organic disease which destroys brain cells.
　　Alzheimer’s disease affects the patient’s memory, speech, and movement. In the beginning stages of the disease, the patient may seem slightly confused. He may have trouble speaking, then the patient’s memory begins to fail. He may forget dates, numbers, names and plans.
As the disease progresses, the patient may not recognize family and friends. These symptoms（症状） often cause terrible anxiety in the patient. He may feel lost and frightened. Sometimes the patient reacts with wild and bad behavior.
　　In the last stages of the disease, the patient may not be able to take care of himself. He may have lost the ability to speak and walk.
　　Scientists don’t know exactly what causes Alzheimer’s disease. It may be caused by a virus.It may be caused by a poisonous substance（物质） in the environment. At present, there is no cure for the disease. But there are ways to slow its progress. Exercise and physical treatment can help the patients of this disease.
【小题1】The main idea of the passage is that Alzheimer’s disease ________.

Once there was an old farmer, with a horse which was almost as old as himself. He __16__ one morning with his young son, 17   the horse before it died. Father and son walked, 18 the farmer did not want the horse to be 19 . ?

They met two men on the road20 said: “Why are you walking, farmer? You have a horse. It's __21__to market.” The farmer knew that this was__22__, so he rode on the horse, __23__his son walked. ?

Then they met two old ladies. “__24__are you doing up there, farmer? Can't you__25__how tired your boy is?” __26__the farmer got down, and his son rode__27__. ?__28__, three old men stopped them. One said: “Why are you walking, farmer?__29__. It's too hot for an old man like you to walk today.” So the farmer got up　 30__his son, and they__31__. __32__, a young woman passed them. “Why aren't you walking?” she asked. “It isn't __33_ to market. Give your poor old horse a rest.”

So the farmer, and his son, got down__34__.

It is a fact that you cannot please__35__the people all the time.