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 Input:
Sentence1: Marine dolphins are endangered by fishing nets, speedboats, and pollution. 
Sentence2: dolphins live mainly in shallow coastal waters.

Ex Output:
dolphins


Ex Input:
Sentence1: Crops are plants that are grown for food or other uses. 
Sentence2: insects destroy plants.

Ex Output:
plants


Ex Input:
Sentence1: lack of moisture in the air causes low amounts of rainfall. 
Sentence2: drought prone areas experience a lack of moisture in the air.

Ex Output:

air