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: exercise increases a body 's strength. 
Sentence2: Exercise is more than running and lifting.

Output: exercise


Input: Consider Input: Sentence1: a light bulb is used for seeing in the dark. 
Sentence2: light is required for seeing.

Output: seeing


Input: Consider Input: Sentence1: During windy weather, the pollution is dispersed and cleared away. 
Sentence2: high pressure systems cause pollution to disperse.


Output: dispersed