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: Bacteria and Viruses Bacteria and viruses can cause diseases. 
Sentence2: bacteria can have a negative impact on an organism.

SOLUTION: Bacteria

PROBLEM: Sentence1: hearing is used for sensing sound by animals. 
Sentence2: functioning ears are used for sensing sound by animals.

SOLUTION: animals

PROBLEM: Sentence1: if an object is black then that object absorbs all visible light. 
Sentence2: melanistic fur absorbs all visible light.

SOLUTION:
absorbs