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: Streams may start with runoff or water seeping out of a spring. 
Sentence2: Most water comes from precipitation.

Answer: water


Question: Sentence1: Earthquakes are natural disasters. 
Sentence2: earthquakes can cause animals to leave an environment.

Answer: Earthquakes


Question: Sentence1: Balance is the ability to sense and maintain body position. 
Sentence2: People fall when they lose their sense of balance.

Answer:
Balance