Sure! Here are the answers to the exercises on the page:
14.1
2. Did you eat
3. has bought
4. did you meet
5. have worked
6. has lost
7. Have you seen
8. has gone
9. have lived
10. has been stolen
14.2
2. I’m not going to eat anything because I have just had lunch.
3. How long have you known Jane?
4. My brother isn’t going to sell his house because he has owned it for a long time.
5. Do you have a holiday recently?
14.3
2. haven’t been / have flown
3. have arrived
4. have just burned
5. have seen
14.4
2. have played
3. have had
4. has toured
5. have competed
6. haven’t won
Let me know if you need further explanation!