TASK DEFINITION: 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.
PROBLEM: Sentence1: Batteries are a better source of DC electricity. 
Sentence2: a flashlight requires batteries to produce light.

SOLUTION: Batteries

PROBLEM: Sentence1: zinc has a positive impact on the healing of wounds. 
Sentence2: oysters have a positive impact on the healing of wounds.

SOLUTION: has

PROBLEM: Sentence1: hiding can be used for avoiding predators. 
Sentence2: camouflauge can be used to avoid predators.

SOLUTION:
predators