小明的外语课老师是一位外籍老师,有一天老师让每个学生说一句话来练习口语。小明心想好了,拍拍桌子大声说到:Why do birds fly south for the winter?老师听了后微微一笑,回答说:That’s a very good question! And because it's too far to walk!(那是个很好的问题啊!因为往南走离这儿太远了!)