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: Specialization decreases mortality 12,13 and increases survival. 
Sentence2: evolving different adaptations increases survival.
[EX A]: increases

[EX Q]: Sentence1: Fish are the first known true chordates. 
Sentence2: Fish are the first known animal with a backbone.
[EX A]: Fish

[EX Q]: Sentence1: Carbon exists as a free mineral in graphite and diamond. 
Sentence2: carbon is in pencil lead.
[EX A]:
Carbon