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.

[EX Q]: Sentence1: Distance is measured in meters the SI unit of distance. 
Sentence2: The SI unit of distance is in meters.
[EX A]: SI

[EX Q]: Sentence1: Human mating behavior also involves some competition. 
Sentence2: Human mating may lead to aggressive behaviors or displays of aggresion.
[EX A]: Human

[EX Q]: Sentence1: being distracted while driving can cause people to crash their car. 
Sentence2: Using a cell phone while driving can cause crashes.
[EX A]:
crash