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: Animals behave in a variety of ways which enhance their chances of survival and reproduction. 
Sentence2: Animals learn to behave to increase chances of survival.
[A]: behave


[Q]: Sentence1: Polyps usually reproduce asexually. 
Sentence2: Polyps usually reproduce several different ways.
[A]: Polyps


[Q]: Sentence1: a speedometer is used for giving a driver feedback on the speed of their vehicle. 
Sentence2: A speedometer can help prevent accidents.
[A]:
speedometer