Forest is related to Trail. Trail is related to Slope. 
Complete is related to Perfect. Perfect is similar to Clear. Clear is related to Day. Day is related to Sunlight. 
Forest <--RelatedTo--> Trail <--RelatedTo--> Slope 
Complete <--RelatedTo--> Perfect <--SimilarTo--> Clear <--RelatedTo--> Day <--RelatedTo--> Sunlight 