mature / matured

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. David is a matured man of forty.
  2. David is a mature man of forty.
  3. He is regarded as mature enough to shoulder responsibility.
  4. He is regarded as matured enough to shoulder responsibility.
    Are these sentences correct?
    Can we use ‘mature’ and ‘matured’ interchangeably ?
    Please comment.
2

In these sentences “mature” is correct. “matured” sounds odd.

When you want an adjectival (rather than verbal) meaning, “mature” is usually the correct choice.