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: Veins generally carry deoxygenated blood. 
Sentence2: Blood carries blood cells.

SOLUTION: blood

PROBLEM: Sentence1: a rainbow is formed by refraction of light by separating light into all different colors. 
Sentence2: Rainbows form when raindrops refract sunlight.

SOLUTION: refraction

PROBLEM: Sentence1: When living things die, they quickly begin to decay. 
Sentence2: Poison causes things to die and quickly decay.

SOLUTION:
decay