郵便箱

1. Origins, structure, and basic meaning

• Structure: 郵便箱, read ゆうびんばこ, means a box for mail.
• Basic usage: The first example refers to a mailbox beside an entrance that receives letters.

2. Common pitfalls and similar expressions

• Reading the box element
  • The standalone word 箱 is read はこ, but the ending of this word is read ばこ.
• How the box is used
  • The example 手紙が届いていた identifies a receiving mailbox. Color alone does not determine whether a box is for sending or receiving mail.