【初中·完形填空·Helping Hands】
阅读下面短文，从各题所给的四个选项中选出可以填入空白处的最佳选项。

Our class decided to visit a nursing home on Saturday. Before we went, our teacher told us: "Do not just work for old people. Do something with them."
I was paired with Grandma Zhang. She could not see well, so I read the news to her. She was interested in everything — the weather, football, even my school meals.
Then she said, "Now let me teach you something." She showed me how to fold paper into a bird. Her hands moved slowly but surely.
On the bus back, we were all tired, but nobody slept. We had learned that helping is not a one-way ______.

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