《吕氏春秋·览·孝行览》
这就好比优秀的农民，他们善于区分土地适宜种植什么，勤勤恳恳地耕种锄草，但未必能有收获。
譬之若良农，辩土地之宜，谨耕耨之事，未必收也。
This is like excellent farmers. They are good at distinguishing which crops the land is suited for, and they diligently cultivate and weed, but they may not necessarily reap a harvest.