题目内容：

A hungry wolf met a house dog when he was looking for food in the forest. The dog looked much stronger than the wolf. So the wolf asked，“My friend，why are you so strong？What food do you eat？”

“If you like，you can be as strong as me，” the dog answered.

“I would do anything to have a warm place to live in.”

“Good. Follow me，” the dog said.

Then they walked to the dog's house. On the way there，the wolf saw a scar(伤疤)on the dog's neck，so he asked the dog about it.

“It's a little thing. Maybe the collar(项圈)made it，” the dog answered.

“You are tied up？” the wolf asked with surprise.

“Just during the day. I am free at night .And people are good to me. They give me delicious food.”

“Good night，” said the wolf.“Enjoy your delicious food. For me，I like being free better than being tied up with a collar.”

1.Where did the wolf meet the house dog？(不超过5个词)

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2.When was the dog free？(不超过5个词)

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3.What does the passage mainly tell us？(不超过15个词)

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