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: Basically, heat is energy. 
Sentence2: Head hair is especially important in preventing energy loss from the body.
[EX A]: energy

[EX Q]: Sentence1: If the skin is painful, seek medical attention. 
Sentence2: If your skin hurts, your touch receptors will sense differences.
[EX A]: skin

[EX Q]: Sentence1: Of all nature's disasters, forest fires are often considered the most frightening. 
Sentence2: Forest fires can cause animals to leave an environment.
[EX A]:
fires