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.

[EX Q]: Sentence1: sonar is used to find the location of an object. 
Sentence2: Surface ships use sonar to locate and track submarines.
[EX A]: location

[EX Q]: Sentence1: Sex hormones are chemical messengers that control sexual development and reproduction. 
Sentence2: Androgens are male sex hormones.
[EX A]: Sex

[EX Q]: Sentence1: Every living thing, animal and plant, are given a classification. 
Sentence2: Cells make up the structure and function of plants and animals.
[EX A]:
animal