疲れる

1. Origins, structure, and basic meaning

• Structure: 疲れる (つかれる) is an intransitive verb for losing energy through activity. The examples show a general result and completed past state.
• Basic usage: Legs tire after climbing a long staircase; a speaker is exhausted after walking all day.

2. Common pitfalls and similar expressions

• Fatigue in a body part and accumulated whole-person exhaustion
  • The first subject is 足が, and dictionary form states a repeatable result. 疲れた gives the speaker's completed state after the day's activity.