N for n
The 'reason' group
These nouns refer to a reason for something.
The usual explanation for this peculiar habit is that the birds are drying their wings after diving to search for food.
The reason for the change is simple.
The preposition for is sometimes followed by an '-ing' clause.
cause excuse explanation ground justification motive rationale reason warrant
Connie did not trouble to invent an excuse for going through her suitcase.