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: People of all ages and activity levels perspire or sweat. 
Sentence2: Perspiration reduces body heat.
[A]: perspire


[Q]: Sentence1: Viruses contain DNA but not much else. 
Sentence2: viruses contain encoded information but not much else.
[A]: Viruses


[Q]: Sentence1: Lengths A length is a measure of distance. 
Sentence2: a ruler is used for measuring  distance.
[A]:
distance