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: Scyphozoans are the next group of Cnidarians, and they are the familiar jellyfish. 
Sentence2: Scyphozoans are aquatic organisms.
[EX A]: Scyphozoans

[EX Q]: Sentence1: the mass of an object causes the gravitational force exerted by that object. 
Sentence2: gravitational force accelerates objects.
[EX A]: force

[EX Q]: Sentence1: Birth may be followed by a period of parental care of the offspring. 
Sentence2: Birth may be followed by parental nurturing.
[EX A]:
Birth