Provide a detailed explanation of the water cycle, including the main stages and how they contribute to the Earth's ecosystem. Your response should contain at least 15 sentences and less than 300 words. Highlight at least two sections in your answer with markdown, i.e. *highlighted section*. Include the keywords: *evaporation*, *precipitation*, *transpiration*, *infiltration*. At the end of your response, please explicitly add a postscript starting with *P.S.*.
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