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: Light is the visible form of electromagnetic energy. 
Sentence2: Electromagnetic energy enters the eye through an opening called the pupil.

SOLUTION: electromagnetic

PROBLEM: Sentence1: a flower 's purpose is to produce seeds. 
Sentence2: Every job has meaning and purpose.

SOLUTION: purpose

PROBLEM: Sentence1: Friction Rubbing an object on another object can produce friction. 
Sentence2: rubbing an object on another object causes the temperature of an object to increase.

SOLUTION:
Rubbing