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: Sound vibrations can be compared to pond ripples. 
Sentence2: dropping an object into water causes pond ripples.

SOLUTION: pond

PROBLEM: Sentence1: Heat and temperature are the same. 
Sentence2: a thermometer is used to measure heat.

SOLUTION: Heat

PROBLEM: Sentence1: True False Fight or flight are extreme responses to stress. 
Sentence2: threatening behavior causes stress in animals.

SOLUTION:
stress