執拗

1. Origins, structure, and basic meaning

• Structure: 執拗 is read しつよう and means being persistent or relentless.
• Basic usage: It is used adverbially for repeated questioning and attributively for a relentless pursuit.

2. Common pitfalls and similar expressions

• Adverbial form
  • 執拗に繰り返した describes repeating the same action persistently.
• Form modifying a noun
  • 執拗な追跡 means a relentless pursuit.