根据短文内容选出空白处的最佳选项

It was Sunday yesterday.

Henry wasn't 1 home. He was on a 2 to the zoo.

An old man got on the bus. Henry stood up and 3 to him, "Come and sit here, please. " He helped the old man 4. "Thanks 5, good boy," the old man said. "You're welcome," said Henry.

The bus went on. Thirty minutes later, it stopped 6 the zoo. Henry got off the bus and said 7 to the old man. The old man smiled (微笑) at him in a friendly way.

Henry went into the zoo. 8 of the people there were students. He 9 a lot of animals and birds, and he also took many photos. He spent a happy weekend 10 he helped others and had a good time in the zoo.