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: Male dogs use pheromones in urine to mark their territory. 
Sentence2: Pheromones are hormones that are thought to stimulate, through smell, sexual reactions in animals.

SOLUTION: pheromones

PROBLEM: Sentence1: Passive immunity lasts only as long as the antibodies survive in body fluids. 
Sentence2: A pregnant woman will pass antibodies to the fetus.

SOLUTION: antibodies

PROBLEM: Sentence1: Animals live on the vegetation found in the biomes. 
Sentence2: Animals can be found to be living in wetlands.

SOLUTION:
Animals