振る

1. Origins, structure, and basic meaning

• Structure: 振る is read as ふる and is a transitive verb for moving an object or body part back and forth or from side to side.
• Basic usage: Mark what moves with を, as in 旗を振る for signaling and 首を振る for shaking one's head.

2. Common pitfalls and similar expressions

• Interpretation depends on the object
  • With a flag it describes waving a signal; with 首, it can indicate refusal through a head shake.
• Difference from 振るう
  • 振る centers on a back-and-forth motion, while 振るう can mean swinging forcefully or exercising an ability.