Fly is related to Bug. Bug can Anger. Anger is related to Hate. Hate would make you want to Kill. 
Collective is related to Crowd. you are likely to find Stranger in/at/on Crowd. Stranger is the opposite of Fellow. 
Fly <--RelatedTo--> Bug --CapableOf--> Anger <--RelatedTo--> Hate --CausesDesire--> Kill 
Collective <--RelatedTo--> Crowd <--AtLocation-- Stranger <--Antonym--> Fellow 