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: intense heat has a negative impact on an organism. 
Sentence2: intense heat has a negative impact on plants.
Example Output: heat

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

Example Input: Sentence1: Autotrophs are organisms that can make their own food. 
Sentence2: An autotroph is a producer that can produce food for itself.
Example Output:
Autotrophs