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.

Q: Sentence1: All lizards are reptiles. 
Sentence2: Lizards are tetrapod vertebrates that produce amniotic eggs.

A: lizards
****
Q: Sentence1: healing requires rest. 
Sentence2: Healing and cell regeneration follows.

A: healing
****
Q: Sentence1: Most people can survive only a few days without water. 
Sentence2: Water controls the body's temperature.

A:
water
****