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.

Example Input: Sentence1: if humans disturb animals in a location then those animals will move to a different location. 
Sentence2: The human being is self-aware.
Example Output: humans

Example Input: Sentence1: Evaporation of sweat uses energy, and the energy comes from body heat. 
Sentence2: Evaporation of sweat uses energy, and the energy comes from exercise.
Example Output: Evaporation

Example Input: Sentence1: Images fill the frame of the camera. 
Sentence2: images in frame will be recorded.
Example Output:
frame