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.
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Question: Sentence1: mountains are formed by earthquakes. 
Sentence2: Mountains are formed by moving plates.

Answer: are


Question: Sentence1: being burried under soil and mud changes peat into coal through extreme heat and pressure in a swamp over a long period of time. 
Sentence2: Marble is used for sculptures, and coal is used for fuel and energy like light.

Answer: coal


Question: Sentence1: Earthworms are important deposit feeders that help form and enrich soil. 
Sentence2: Earth stands for soil, dust or ground.

Answer:
soil