instruction:
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.
question:
Sentence1: All frogs are amphibians. 
Sentence2: frogs have permeable skin that easily absorbs substances from the environment.
answer:
frogs


question:
Sentence1: Mammalian teeth are important for digestion. 
Sentence2: bats' teeth are important for digestion.
answer:
digestion


question:
Sentence1: Wound healing Wound healing is a critical aspect of surgery. 
Sentence2: zinc has a positive impact after a surgery.
answer:

surgery