Answer:
    The last time he visited his parents was 1 month.
    He hasn't visited his parents for 1 month.
2. We haven't eaten fish for 5 days.
  The last time we ate fish was 5 days.
  We last ate fish 5 days ago.
 3. We last wrote a book many years ago.
   The last time we wrote a book was many years.
   We haven't wrote a book for many years.
4. He last talked to her over a month ago.
  The last time he talked to her was over a month.
  He hasn't talked to her for over a month.
Explanation:
