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: Lions live in social groups called prides. 
Sentence2: Chimpanzees live in social groups called communities.

A: groups
****
Q: Sentence1: Average vehicle speed rises by only 0.3 miles per hour. 
Sentence2: a speedometer measures miles per hour.

A: hour
****
Q: Sentence1: Adolescence is the last stage of life before adulthood. 
Sentence2: Adolescence is a pivotal stage of human development.

A:
Adolescence
****
