後

1. Origins, structure, and basic meaning

• Structure: 後 is a noun read あと, meaning after in time or behind in space.
• Basic usage: It can locate an action after a meal or people in a line behind the speaker.
  • 食事の後で短い散歩をした。 says that the speaker took a short walk after the meal; 私の後に三人の客が並んだ。 says that three customers lined up behind the speaker.

2. Common pitfalls and similar expressions

• 食事の後で
  • 後で places the walk after the meal in time.
• 私の後に
  • 後に marks the three customers' position as behind the speaker in the line.
• 後 and 前
  • 後 means later in time or behind in space, while 前 means earlier or in front.