David Smith taught science at the city school. He needed some modern books and bought them. He put the books in his car in a quiet street. Then he went to buy something else. When he came back to the car, he found that one of the car’s doors was open, the books weren’t there! David drove home. That night he wrote a letter to the newspaper. The next day he went to the police station and offered the list of the lost books. On Friday, people read this in the newspaper:

David stayed at home on Saturday. The policeman came at eight. David took him to the kitchen. One hour later, another man arrived. He had a bag under his arm.

“Mr. Smith?” the man asked.

“That’s right,” David said. “Can I help you?”

“I’ve got some good books. You want to buy books, don’t you?”

“Yes. Bring them in. Let me have a look.”

Soon the books were on the table. “Come in now,” David called. Then the policeman came in with the book list. He read the names on the books and the names on the list. They were the same.

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76. David Smith was a         teacher at the         school.

77. On Saturday, the policeman came at      o’clock, another man arrived

at      o’clock.

78. In fact, David didn’t          to buy some old and modern books after his books were _______________.

79. David thought of a         way to find out the man who         the books.

80. There were         people in the story. They were David, the         and the thief.