You can forget grammar completely but write the consequence of your thought and scene. Linguists call this a topic-comment language: 雨下, 人疏 -> [as for when it]

You can forget grammar completely but write the consequence of your thought and scene. Linguists call this a topic-comment language: 雨下, 人疏 -> [as for when it] rains, [there are] fewer people [out]. It does makes for some nice poetry.