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.

Q: Sentence1: friction causes the temperature of an object to increase. 
Sentence2: pressure causes the temperature of an object to increase.

A: causes
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Q: Sentence1: cell division often causes growth. 
Sentence2: Cell division leads to reproduction.

A: cell
****
Q: Sentence1: Asses are great runners and there is no match in speed and stamina in the entire animal kingdom. 
Sentence2: asses require stamina to succeed at running.

A:
Asses
****