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: when a body of water receives more water than it can hold , a flood occurs. 
Sentence2: Floods are deadly, floods are devastating.

Ex Output:
flood


Ex Input:
Sentence1: Most major Atlantic hurricanes start as small disturbances moving westward off Africa. 
Sentence2: When something that starts as a small disturbance moving westward off Africa then moves over land, it will decrease in strength.

Ex Output:
Africa


Ex Input:
Sentence1: Animals are a kingdom of multicellular eukaryotes. 
Sentence2: plants and animals are multicellular.

Ex Output:

Animals