根据下列句子的意思及所给单词的首字母或所给汉语意思,写出各单词的正确形式.每空一词.

1. The food smells d_________________. Why not go to taste it?

2. Please take the m_________ three times a day, and you’ll be OK soon.

3. There is too much n__________. Let’s find a quiet place to rest in. 

4. By the end of the _______(二十) century, the world population had passed six billion.

5. My teacher often __________(鼓励) us to practice English as often as possible.

A farmer had a cow. He took very good care of this cow and one day when it was ill, he was very worried. He telephoned the vet.
　　“What’s the problem?” The vet asked him when he arrived.
　　“My cow's ill,” the farmer said. “I don’t know what's the matter with her. She’s lying down and won’t eat. She's making a strange noise.”
　　The vet looked over the cow. "She's certainly ill," he said, "and she needs to take some very strong medicine." He took a bottle out of his box, put two pills into his hand and said, "Give her these. The pills should make her better."
　 “How should I give them to her?” the farmer asked.
　　The vet gave him a tube (管子)and said, "Put this tube in her mouth, then put the pills in the tube and blow. That'll make it."
　　The next day the vet came to the farm again. The farmer was sitting outside his house and looked more worried.
　　“How's your cow?” the vet asked.
　　“No change,” the farmer said, “and I’m feeling very strange myself.”“Oh?” the vet said, "Why?"
　　“I did what you said,” the farmer answered. “I put the tube in the cow's mouth and then put two pills down it.”
　　“And?” the vet asked.
　　“The cow blew first,” the farmer said.
48.In the story, the vet must be _________.
　　A. the farmer's friend    B. a milk factory  C. a hospital for cows   D. a doctor for animals
49.What medicine did the vet give the farmer?
　　A. Bottle of pills.    B. A long tube.   C. Two pills.    D. A small box.
50.The vet taught the farmer how _________.
　　A. to blow the tube             B. to make the cow take the pills
　　C. to take the medicine         D. to put the tube in his mouth
51.Which of the following is true?
　　A. The farmer ate the pills himself.　　B. The cow got better after taking the medicine.
　　C. The vet came to help farmer change the cow the next day.
　　D. The farmer waited for the vet outside his house the next day.