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: Animals can communicate with sounds, chemicals, or visual cues. 
Sentence2: cats can communicate with sounds, chemicals or visual cues.

Answer: chemicals


Question: Sentence1: With a spatula, fold in flour mixture. 
Sentence2: a sifter is used for separating flour.

Answer: flour


Question: Sentence1: Fertilization occurs when a sperm and an egg fuse to form a diploid zygote. 
Sentence2: An embryo created in the fertility process is human life.

Answer:
Fertilization