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: Plants use unsaturated fatty acids to store energy. 
Sentence2: Plants and fish contain fatty acids.

Answer: Plants


Question: Sentence1: Any antigen that causes an allergy is called an allergen. 
Sentence2: molds are antigens.

Answer: antigen


Question: Sentence1: Legumes are typical of that type of plant. 
Sentence2: legumes grow towards a light source.

Answer:
Legumes