kāitóu ràng rén zhīdào shuǐ cóng nǎlǐ lái zhōngjiān dài zhe tīngzhòng wǎng qián zǒu jiéwěi ràng rén kàn dào tā liú xiàng nǎlǐ

开头让人知道水从哪里来，中间带着听众往前走，结尾让人看到它流向哪里。

The beginning tells where the water comes from, the middle leads the audience forward, and the end shows where it flows.