What you must bear in mind?
01. Inspect your tables
2. Group all the obvious fields that are the same entity or linked together.
3. Ensure you have the tables that are stated in scenario
4. The remaining field can be grouped together using composite keys
5. Composite keys can be a. Keys within that fields for example a) "Cleanliness rating" could depend on 1. No of clean ups per year, Amount of rubbish cleaned , Year of the review
b, It can depend on a foreign composite keys - You decide!