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: Dilation occurs when cell walls relax. 
Sentence2: Decreased oxygen levels cause blood vessels to dilate and cell walls to relax.

SOLUTION: relax

PROBLEM: Sentence1: Mammalian predators include the coyote and bobcat. 
Sentence2: a coyote's teeth is important for digestion.

SOLUTION: coyote

PROBLEM: Sentence1: riding a bike does not cause pollution. 
Sentence2: Pollution One of the ways habitat is degraded is by pollution.

SOLUTION:
pollution