fertile

1. Origins, structure, and basic meaning

• Structure: 沃 has 7 strokes and appears in words describing fertile land.
• Basic usage: 肥沃 is read ひよく, and 沃土 is read よくど.

2. Common pitfalls and similar expressions

• A quality and the land itself
  • 肥沃な土地 modifies land with the quality of being fertile.
  • 沃土 in 沃土が広がっていた is a noun referring to fertile land.
• に marking a result
  • 土を肥沃にする means making soil fertile, with 肥沃に expressing the resulting state.