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: Skin color is another polygenic trait. 
Sentence2: Skin color is influenced by multiple genes.
[EX A]: Skin

[EX Q]: Sentence1: freezing means changing from a liquid into a solid by reducing heat energy. 
Sentence2: Water freezes into ice when cooled.
[EX A]: freezing

[EX Q]: Sentence1: Rainbows have colors because water refracts different wavelengths of light slightly differently. 
Sentence2: Rainbows are formed from light hitting water and refracting different wavelengths.
[EX A]:
different