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: Endospores are commonly found in soil and water. 
Sentence2: Dirt is really misplaced soil.
Example Output: soil

Example Input: Sentence1: If there is no movement friction is zero. 
Sentence2: Movement causes the temperature of an object to increase.
Example Output: movement

Example Input: Sentence1: some flowers become fruits. 
Sentence2: Fruit can be made into fruit leather.
Example Output:
fruits