very perfect in English:

flawless complexion/performance

If your English is perfect, it is flawless

The deal is not flawless, however.

He is always flawless.

Your last piece of work was absolutely flawless. Well done!

This is the most beautiful diamond I've ever seen. It's flawless.

The countdown was flawless, and the space missile went off exactly on schedule.

He who seeks a flawless horse or flawless wife, may rest assured that even if his work he did forsake, nor bed nor stable would he ever fill.