1. I haven't enjoyed so much for years.

=> It is years since I last enjoyed.

2. He has not had his hair cut for over six months.

=> It is over six months since he last had his hair cut.

3. How long is it since they bought the house ?

=> When did they buy the house?

4. I've never met such a famous person before?

=> It is the first time I have (ever) met such a famous person.

5. I haven't eaten this kind of food before.

=> This is the first time I have eaten this kind of food.

1. It is years since I last enjoyed.

2. It is over six months since he last had his hair cut.

3. When did they buy the house?

4. It is the first time I have met such a famous person.

5. This is the first time I have eaten this kind of food.