a retentive soil的用法和样例：
- He is a scholar who has wide learning and a retentive memory.
- I have a retention feeling after urinating.
- He was acutely observant and had a retentive memory. He was particularly good at capturing images and had an eye for minute detail.
- There are a lot of worms in the soil.
- The soil absorbs only a fraction of the rain that beats down.