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—Yes, but now he's used to ________the bus.

    Do you know running is getting more and more popular these days, a lot of people run for health. Doctors say many health problems come from these bad habits: eating and drinking too much, smoking, and not taking enough exercise. Doctors tell us, "Eat and drink less, don't smoke, and exercise more."

    Running is a good form of exercise because it helps build a strong heart. It also helps most people lose weight. One 68-year old woman runs three times a week. "I love eating" she says. She runs to lose weight. Running is good for health in other ways too. Many runners say running keeps colds away. Running can also help people to relax. So today men and women of all ages enjoy running.

    Teeth are a key part of your body. Strong, healthy teeth help you chew all kinds of foods that help you grow. They help you speak clearly. That's why it's necessary to take great care of your teeth. The following suggestions help you have healthy teeth for life.

    One is to brush your teeth at least twice a day, more often if possible. You'd better brush your teeth after every meal, especially a sweet snack, which is the best way to protect against tooth disease(疾病). It's necessary to clean the front, back and top surfaces of all your teeth.

    Another step you can take to protect your teeth is flossing. Floss is a thin thread(丝线)that moves between teeth to remove food that your toothbrush can't reach.

    You should pay attention to what you eat. Eating foods that are high in sugar can lead to tooth disease. That's because bacteria that causes tooth disease loves sugar. You can eat fruits and vegetables instead which are good for your body as well as your teeth.

    Healthy teeth will always bring you happiness. Do you want to have white and healthy teeth? Please take care of your teeth!