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.

[EX Q]: Sentence1: threatening behavior by predators causes a porcupine to extend its quills. 
Sentence2: Fishers are one of the few specialized predators on porcupines.
[EX A]: predators

[EX Q]: Sentence1: Blood type is important for medical reasons. 
Sentence2: Type O is important for medical reasons.
[EX A]: important

[EX Q]: Sentence1: Animals can communicate with sounds, chemicals, or visual cues. 
Sentence2: Animals can communicate with energy.
[EX A]:
Animals