Ответ:

  1. I’m very much grateful to you.
  2. Let me introduce my brother to you.
  3. Please, give your wife my regards.
  4. You are very kind.
  5. We say “good evening” after 17 o’clock.
  6. It’s a great pleasure to meet you.

Ответ: 1) grateful; 2) introduce; 3) regards; 4) kind; 5) good evening; 6) meet.