not

1. Origins, structure, and basic meaning

• Structure: 不 has four strokes and contributes a negative or insufficient sense; its main on reading is ふ.
• Basic usage: It forms part of compounds such as 不便, 不安, and 不足, whose meanings are learned as complete words.

2. Common pitfalls and similar expressions

• Word formation and sentence negation
  • 不 cannot be freely placed before any word or verb to negate a sentence.
  • 便利ではない is a phrase meaning “not convenient”; 不便 is a separate word meaning inconvenience.
• Anxiety beyond simple negation
  • 不安, read ふあん, describes worry or a lack of reassurance.
  • Reducing it to “not safe” can lose its meaning as an emotional state.
• Not enough
  • 不足, read ふそく, means falling short of a required amount or degree.
  • 説明が不足している means the explanation is insufficient, not necessarily that there is no explanation at all.