Here are the identified false parts and their corrections:

1. **She has broken her leg the day before her exam.**
- Correction: **the day before** → **the day of** (or specify a clearer time reference)

2. **King Henry the Eighth of England had six wives.**
- Correction: No correction needed (correct as is).

3. **Victor and Jackie have not known each other for years and years. They are very good friends.**
- Correction: **have not known** → **have known**

4. **I met them when I was in Paris. It has been in 1988.**
- Correction: **It has been** → **It was**

5. **We have had that black dog since many years. I think my mother bought it right before I was born.**
- Correction: **since many years** → **for many years**

6. **We were really happy in those days. Many things changed.**
- Correction: No correction needed (correct as is).

7. **He has slept for just a quarter an hour only. Don't wake him up.**
- Correction: **for just a quarter** → **for just a quarter of an hour**

8. **Did he met her in the street a moment ago?**
- Correction: **met** → **meet**

Feel free to ask if you need further assistance!