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.

Example Input: Sentence1: Germination depends on the seed coat. 
Sentence2: the force of water causes germination with the emergence of a root.
Example Output: Germination

Example Input: Sentence1: nectar is used for attracting pollinators by plants. 
Sentence2: butterflies pollinate plants.
Example Output: plants

Example Input: Sentence1: Annelids include earthworms and leeches. 
Sentence2: earthworms have the amazing capacity to regrow segments that break off.
Example Output:
earthworms