Boy is related to Toy. Toy is related to Present. 
Soldier can be used for Protection. Protection is related to Helmet. Helmet is related to Hat. Hat is related to Sun. 
Boy <--RelatedTo--> Toy <--RelatedTo--> Present 
Soldier --UsedFor--> Protection <--RelatedTo--> Helmet <--RelatedTo--> Hat <--RelatedTo--> Sun 