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: if an object is kicked then force is exerted on that object. 
Sentence2: if an object is kicked then a measurement of newtons is exerted on that object.
[EX A]: exerted

[EX Q]: Sentence1: An accounting period is simply a period of time. 
Sentence2: seconds are used to measure a period.
[EX A]: period

[EX Q]: Sentence1: Ocean thermal is energy derived from waves and also from tidal waves. 
Sentence2: Ocean thermal can be used to produce electricity.
[EX A]:
Ocean