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: Insect wings are attached to the dorsal side of their thorax. 
Sentence2: wings are attached to the dorsal side of the insect.

Output: dorsal


Input: Consider Input: Sentence1: if an organism becomes too hot then that organism may die. 
Sentence2: if an organism overheats then that organism may die.

Output: die


Input: Consider Input: Sentence1: An abalone is a shellfish or mollusk. 
Sentence2: abalones are a major food source for humans.


Output: abalone