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: a sifter is used for separating mixtures. 
Sentence2: a sifter is used for some recipes.

Answer: sifter


Question: Sentence1: An intense bright light produces a glare. 
Sentence2: Nuclear reactions in stars cause stars to produce bright glares.

Answer: bright


Question: Sentence1: Cells are organized into tissues, and tissues form organs. 
Sentence2: Stem cells are cells that can become many tissues and organs.

Answer:
tissues