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: weathering means breaking down rocks from larger whole into smaller pieces by weather. 
Sentence2: Trash collectors work in all types of weather, including rain and snow.

Output: weather


Input: Consider Input: Sentence1: Cells are the units of function in living things. 
Sentence2: living things cannot survive without oxygen.

Output: living


Input: Consider Input: Sentence1: pollutants have a negative impact on the environment. 
Sentence2: Environment and Health Environment and Health All living things depend on their environment.


Output: environment