Smooth sailing: (a thousand miles in a day)? (2) The mountain is high and the water is long: (Flying down three thousands of feet)? I met Yan Gui/we met. We understand. What is the relationship between acquaintances? /Everyone knows Jun)? (4) Out-of-water hibiscus: (Xiao He only shows sharp corners)
Supplement:
You can't shoot "Straight from my Yun Fan, the deep sea under the bridge" or "Alone in the blue sky" when things are smooth, because when the riddle and the answer are repeated, it is not a good riddle.
Similarly, water hibiscus can't shoot "clear water gives hibiscus".