Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.

Sentence1: Aggression is behavior that is intended to cause harm or pain. 
Sentence2: Verbal violence is behavior that is intended to cause harm or pain.
behavior

Sentence1: Heterotrophs get food by eating other living things. 
Sentence2: fish eat other living things.
living

Sentence1: Insects also have both a heart and a respiratory, or breathing, system. 
Sentence2: a mold spore has a negative impact on breathing.

breathing