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: high pressure systems cause clear weather. 
Sentence2: Weather Clear weather usually means good visibility.

Answer: clear


Question: Sentence1: An accounting period is simply a period of time. 
Sentence2: seconds are used to measure a period.

Answer: period


Question: Sentence1: Some parasites kill their host, but most do not. 
Sentence2: most tapeworms do not kill their host.

Answer:
do