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: heating an egg causes a chemical reaction in the egg. 
Sentence2: Insects hatch from eggs.
[EX A]: egg

[EX Q]: Sentence1: First, the bottle is calibrated with a graduated cylinder. 
Sentence2: calibration is performed with a cylinder.
[EX A]: calibrated

[EX Q]: Sentence1: Internal migration describes moves within a country. 
Sentence2: Gene flow occurs when individuals migrate.
[EX A]:
migration