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: Most copepods feed on phytoplankton. 
Sentence2: most copepods feed on bacteria and algae that use sunlight to make food.

Answer: copepods


Question: Sentence1: the emission of sulfur dioxide causes acid rain. 
Sentence2: Sulfur dioxide emissions causes soil nutrients to be leached away.

Answer: dioxide


Question: Sentence1: Ice is a solid, it's cold and it's hard. 
Sentence2: Melting occurs when ice is heated above its melting point.

Answer:
Ice