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: Antigens are proteins foreign to the body. 
Sentence2: antigens are proteins.

Answer: proteins


Question: Sentence1: Insect wings are attached to the dorsal side of their thorax. 
Sentence2: wings are attached to the dorsal side of the insect.

Answer: dorsal


Question: Sentence1: Hurricanes A hurricane is a type of tropical cyclone. 
Sentence2: A tropical cyclone can convert heat energy into mechanical energy.

Answer:
cyclone