単純

1. Origins, structure, and basic meaning

• Structure: 単純 is read as たんじゅん and is a な-adjective and noun for a structure or process that is not complicated.
• Basic usage: Use 仕組みは単純だ predicatively and add な before a noun in 単純な作業.

2. Common pitfalls and similar expressions

• Predicative and attributive forms
  • At the end of a clause it appears as 単純だ; before a noun it changes to 単純な.
• Simplicity and carelessness
  • A simple task does not make checking unnecessary; the example warns that precisely such tasks can be easy to overlook.