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: an image in a mirror is formed by reflecting light. 
Sentence2: mirrors can be seen with our eyes.
[EX A]: mirror

[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: Some species of reptiles can go several weeks between meals. 
Sentence2: some snakes can go several weeks between meals.
[EX A]:
Some