• Purple Didn't even know what foil was, just guessed things that can be used for covering stuff.
• Yellow Disregarded final as there are multiple finals not one. And then thought of a ball as in celebration at the graduation or something.

For yellow I though something about air like

• dead air
• cold air
• wet air?
• windy air?

Purple – farm buildings

• smack → shack
• barm → barn
• rankle?
• lear?

I had an idea for green, but dead was taken and smack was sort of taken.
Blue, feels like a strech even with the group.