—I_____ you not to tell others about that.

—She wants me to ________ my sister's writing and learn from her.

Is your family interested in buying a dog? A dog can be a1companion（伙伴） to your family, but if you choose the wrong kind of dog，you will have a lot of2. Families should sit down and thoroughly discuss the possible problems before3a dog. Even if the children in your family are the ones who want the dog, the parents are the ones who are really responsible for seeing that the animal is properly4. If you don't know much about dogs, it is a good idea to go to the5for books about different kinds of dogs, as well as books about how to train a young dog. In reading about the6breeds(种类)you should know that a dog described(描述)as very alert(机敏灵活的)may be too active. When a book describes a dog as an excellent hunting dog, it probably means that the dog won't be happy living in a7house. Dog breeds vary(变化)in popularity as the years go by. One of the most popular dogs these days is the German shepherd（牧羊犬）. This is because it8protection as well as companionship（陪伴）. The family should be warned that these dogs grow up to be very big, and may be too9for children to control. If space is limited, a toy dog may be a good choice. These dogs are very small and10to train. They don't need to be walked daily, since they can exercise in the home.

One day, a little white rabbit went to a bakery and asked, "have you got 100 buns(小面包)?"The shopkeeper answered," sorry, we don't have that many" "oh, that's a pity!" said the rabbit and left disappointed. The second day the little white rabbit went to the bakery again and asked," have you got 100 buns?" The shopkeeper again answered," sorry, we don't have that many" "oh, that's a pity," said the rabbit, and again left, disappointed. The third day the little white rabbit went again to the bakery and asked. "have you got 100 buns?"," oh, yes, we have 100 buns today!" the shopkeeper answered gladly." "that's great, I'll buy two, thank you!" the shopkeeper stood silently.

George Stephenson was born in 1781 in a poor family. He had to start work when he was only eight. When George was fourteen, he became his father's helper. He spent a lot of time learning about engines. And on holidays he often took one to pieces and studied each piece carefully. Soon he became a very good worker though he could not read or write. He began to learn the English letters when he was seventeen years old. Every day after he did twelve hours of hard work, he walked a long way to have lessons from a young school teacher. On his eighteenth birthday, he wrote his own name for the first time in his life. George invented many things in his life. The train was the greatest one among them. Today when we watch or take trains from one place to another, we will think of this great man -- George Stephenson.

Zu Chongzhi was a Chinese mathematician, astronomer and mechanic. He was born in a well-educated family. As excellent engineer, Zu's grandfather taught him science. From an early age, Zu (show) great intelligence and curiosity, with special interests mathematics and astronomy. Today we know Zu Because he was the (one) person to find out that pi falls between 3.1415926 and 3.1415927, and his result remained tht most accurate value in the world for more than 900 years. Zu also worked out the close value of pi to be 355/113, which he called "close ratio". This ratio was so hard to get a Japanese mathematician named it "Zu's ratio".

It is not clear how Zu became interested in (find) the value of pi, yet people have told stories about him. For a long time in the past, people believed that a circle's circumference was three times its diameter. Zu was not sure about this result and wanted to prove it (he). He used a rope (measure) the circumference of a wheel. Then he folded the rope into three equal parts and compared it with the diameter of the wheel. No matter how many wheel he measured, the diameter of the wheel was always (short) than a third of the circumference. As a result, Zu decided to work out a more accurate ratio. After years of hard work, he (final) worked out the value of pi.