Uncle Sam didn’t feel like eating anything because he had     21     toothache. So he went to the hospital in his village.

“What’s the matter, Sam?” Dr. Smith asked. “I don’t feel well these days, and one of my teeth     22    （hurt）,” Uncle Sam answered. Dr. Smith examined（检查）him carefully but didn’t find any trouble     23     Sam.

“Do you smoke?” Dr. Smith asked. “No. In fact, I gave     24     smoking several years ago,” Uncle Sam said. “Do you drink wine（酒）?” “No, I     25     drink wine. It’s not good for my health. I know the importance of     26    （healthy）,” Uncle Sam said.

Dr. Smith thought for a while and then asked, “Do you like eating sweet food?”

“Yes, I like all sweet things. I am used to     27    （eat）a piece of cake every day,” Uncle Sam answered.

“That’s the problem. Now you should     28    （control）the amount（量）of sugar that you have every day. Take this medicine three     29    （time）a day and you’ll feel better soon,” said Dr. Smith with a smile. Hearing that, Uncle Sam made a     30    （decide）to stop eating sweet food.

Kalie missed school but she couldn’t go. She felt tired. Her throat was really sore and her nose kept running. Kalie sat on the sofa, wrapped up in a quilt. She just couldn’t get warm! “You feel hot. A flu virus (病毒) must have caught you!” said Kalie’s mom as she felt Kalie’s forehead. “A flu what?” “A flu virus. It’s so small that you can’t even see it!” “But how could something so small make me sick?” “Well, good question. Once a virus gets into your body, it finds a cell. It forces that cell to make more of the virus. As more and more of the virus is made, it spreads throughout your body.” “And that makes me ill?” “Kind of. The things you feel, like your fever, your runny nose…that’s your body fighting off the virus!”

“You need to drink more water when you have the flu.” Kalie drank some of her hot tea. “So, there’s a fight going on inside me?” “Yes,” said her mom. “And you’re doing two of the best things you can do. Drink clear water and rest!”

“I texted Sonja. She says that some other kids in our class got the flu, too. But not her. She got a vaccine (疫苗). Is that true, Mom?” “Oh, yes. A vaccine gives you a tiny bit of the virus, not enough to make you sick, but just enough to allow your body to know the virus and learn how to protect itself.”

“So if I got a vaccine, I wouldn’t get the flu?” “That’s right,” Kalie’s mom stopped. She looked sad. “Sorry, we didn’t get the vaccine this year. But we will for sure next year!”