If you are riding a bike in foreign countries, you need to know what these traffic signs mean.

1		This sign means “walk”, you can cross the street along with other people.
2		This sign is the “don't walk” sign. It means you should stop to wait for a while until the sign of “walk” is showing.
3		This sign means that there is a bike lane. If you see such a sign, you must use the bike lane.
4		Car drivers and bike riders must come to a complete stop at “STOP” signs.
5		This sign means you are coming to a zebra crossing. You must slow down to allow people in the zebra crossing to cross the street.
6		This sign means parts of the road are rough. Be careful! Rough roads make you fall off your bike.

根据其内容简略回答问题。

    Canada Geese are large blue and white birds. When autumn comes, they have to fly south where the weather is warmer. The winters are so cold in Canada that the birds will die if they stay there.

    Last spring, Bill Lishman found sixteen young Canada Geese on his farm. They had lost their parents. Bill thought, “These young birds won't know what to do in the autumn.” He had a small plane and he decided to teach the birds to fly by following him. All through the summer, he went on short trips in his plane and the young geese flew after him.

    When the cold weather arrived in the autumn, Bill flew to Virginia in the United States--600 miles south of his home in Canada. The geese followed him all the way. Bill left the geese in Virginia and he returned home. This spring, Bill was waiting for the birds to come back. They didn't arrive, so Bill flew to Virginia to get them. He looked for them for two weeks but he couldn't find them. When he arrived back home, he found the geese waiting for him. They had found their way home without him!

    Traveling（旅行) is one of the most important activities and people were interested in it many years ago. Modern traffic develops(发展) fast, so traveling to different places has become much faster than before.Staying healthy while traveling can make your trip happier. But do you know how to keep healthyduring a trip? The following advice may be useful to you.

    Before leaving

①Wear comfortable shoes, a hat and sunglasses.

②Take some medicine that you need with you. They can be used when you get ill or have other problems.

③Do some exercise for weeks or months before you leave if you plan to do lots of walking or climbing during your trip.

④Prepare（准备） proper (适当的)food. Take bread, biscuits and some fruit for a long time. They don't go bad quickly. Bring meat, fish, eggs, milk and even salads and vegetables for a nearer one.

While traveling

①Be sure not to eat dirty food or bad fruit.

②Have enough time to take a rest during your trip.Itcan help you become more relaxed.

③Tap（水龙头）water is not safe, so drink bottled water and always clean the cover of the bottle.

④Keep food in good condition（状态）. Remember: If you travel with food, keep hot food hot and cold food cold.

    Noise pollution is doing much harm to our health now. Noise，in fact，is unwanted sound and is a kind of invisible (无形的) killer. More and more students enjoy listening to music very much. When they listen to MP3 players, they like to turn up the volume (音量). Some people love listening to loud music. Furthermore, while watching TV, they keep the volume up. But they haven't realized that the noise is weakening their hearing. In fact, the noise not only influences each member in the family, but also makes a difference to the comfort of neighbors.

    Noise pollution is a source of increasing misery (痛苦) to people in our society. If people are often disturbed by it, they may feel uncomfortable or upset. What's worse, the noise can make people mad sometimes. If a worker works in a printing factory for too long, his/her hearing loss is much faster than a common person working in a quieter environment. So everybody must pay more attention to noise pollution. Generally speaking，the following four types of noise should be watched out for：

    Noise in the street

    Construction site (建筑工地) noise

    Noise at work

    Transportation noise

    I think the local department (部门) should take measures to control the noise levels, but it's everybody's duty to keep a quiet environment.

    Do you know the whales in the sea? There are many relatives(亲属) in the whale family and they always live together with whales.

    Few people know dolphins(海豚) are part of the whale family. Dolphins are not fish. They are mammals(哺乳动物). They breathe air, and they have babies and feed them with milk. Dolphins are famous for their wonderful shows. They can jump high out of the water and show turns in the air. These jumps give the dolphins time to breathe.

    Porpoises(鼠海豚) are also in the whale family and are quite like dolphins. But they are different in the size and shape of the mouth. The dolphin's mouth is long and thin, but the porpoise's is short and thick. Dolphins are also more talkative than porpoises. Dolphins make sounds to talk with each other under water. But porpoises do not do this. Both of them are smart and friendly to humans.

    Not all the members of the whale family are friendly. Big whales are much easier to be angry than smaller dolphins or porpoises. An angry whale can be dangerous. Perhaps this helped to create the story of Moby Dick that sank (使下沉) a ship and made all the people on it die in the sea.