用螺旋测微器测量金属丝的直径，把金属丝放在已校准的螺旋测微器的测砧和测微杆之间，

Dick was born in a poor family. His father had a small boat and went fishing in the morning and sold the fish in the market in the afternoon. Then he bought some food for his family. When winter came, they were often hungry. One morning the hungry man fell into the river and wasn't found. 小题1:___________ His aunt had to look after him.
　　Twenty years passed. 小题2:___________ He found work on a farm. He worked hard and wanted to get more money. 小题3:___________ The woman was very happy but one day she died in a traffic accident. The young man was very sad. After he buried her, he decided to buy a beautiful tombstone(墓碑) for her. 小题4:___________, but all the tombstones were too expensive. He asked, "Do you sell an old tombstone, sir?" "Yes, we do, sir, " answered the shopkeeper. "Is it as expensive as the new one?"
　　"No, it's much cheaper," said the man. "小题5:___________ " "It doesn't matter, " said Dick. "My aunt couldn't read. "

A. Dick became a tall, strong man. B. But another name was engraved(刻) on it. C. He went to town and came in a shop D. Dick's mother left her three-year-old son without saying good-bye. E. He often went to see his aunt with some nice presents.