More and more Americans are going to work by bike. Do you know why more people are  1   bikes to work? We can answer the question in  2  ways. First, bikes don’t need gasoline (汽油), so it takes  3  money to use them. Second, a bike doesn’t  4 much space (空間), so it is  5 to find a place for it. And riding a bike is good for one’s  6 . People often drive their 7 to offices or to shops, but now people think riding bikes is a good way of doing sports.
That’s  8  more Americans are now riding to work  9  bike, and they are  10  their own cars at home.

As a kid, everyone wants to learn how to ride a bike. Here is some advice to_1_ you be on your way.
The bike. Start with a bicycle and it’s small enough for your feet to touch the _2_. If you lose your balance, you can put your feet to the ground _3_.
Training grounds. You need a big place for the first part of your practice. Be sure to wear something to keep _4_.
Keeping your balance. It’s very important to learn how to keep your balance. You may practice this easily. _5_ your bike to the higher place. Sit on the bike seat  _6_both feet on the ground. Lift both feet a few inches to let the bike roll down. If you start to fall, just put your feet on the ground. Try practicing this several times _7_ you get your balance.
Pedaling(踩動). After you get your balance, it’s time to _8_ learning how to pedal. Start by sitting on the bike seat. With your left foot on the ground and your right foot on the pedal, then push _9_ on the pedal. Push off with your left foot. Keep on practicing until you learn it well.
Braking(剎車). Catch them lightly at first, slowly increasing the pressure to get to a full _10_. Remember that braking hard while going fast can cause you fall over.