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: Cnidarians are invertebrates such as jellyfish and corals. 
Sentence2: Jellyfish and corals are radial, tentacled animals that live mostly in the seas.

Output: corals


Input: Consider Input: Sentence1: Precipitation falls on the windward side of the mountain range. 
Sentence2: Mountains have higher precipitation than adjacent lowlands.

Output: Precipitation


Input: Consider Input: Sentence1: All animals are heterotrophs. 
Sentence2: All fish are animals.


Output: animals