不注意

1. Origins, structure, and basic meaning

• Structure: 不注意 is read as ふちゅうい and functions as a noun or な-adjective for carelessness or insufficient attention.
• Basic usage: Cause appears in 不注意で皿を割る, while carelessness as the source of a result appears in 不注意が事故につながる.

2. Common pitfalls and similar expressions

• Cause and result
  • 不注意で marks carelessness as the reason something happened, while 不注意が presents it as what leads to a result.
• Difference from 油断
  • 油断 is letting one's guard down, while 不注意 broadly means failing to give necessary attention.