外

1. Origins, structure, and basic meaning

• Structure: Spelling: 外. Reading: そと. Core meaning: outside; exterior.
• Basic usage: Representative examples: 雨がやんだので、外へ散歩に出かけた / 箱の外に名前を書いておいてください.

2. Common pitfalls and similar expressions

• Direction and location outside
  • 外へ marks direction toward the outside, while 外に marks a location outside. The particle distinguishes movement from a relation of presence or placement.