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.

Input: Consider Input: Sentence1: Some birds are pollinators that co-evolved with plants. 
Sentence2: insects pollinate plants.

Output: plants


Input: Consider Input: Sentence1: hiding can be used for avoiding predators. 
Sentence2: Camouflage is used for avoiding predators.

Output: avoiding


Input: Consider Input: Sentence1: Centrioles are organelles involved in cell division. 
Sentence2: Centrioles come in pairs.


Output: Centrioles