人教版小六英语上册第六单元The story of the rain的课文中回答该问题：It comes from the clouds.
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Where does the rain come from?It comes from the clouds.
Where does the cloud come from?It comes from the vapour.
Where does the vapour come from?It comes from the water in the river.
How can the water become vapour?The sun shines and the water becomes vapour.