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.

Q: Sentence1: pathogens can cause disease. 
Sentence2: pathogens affects the immune system.

A: pathogens
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Q: Sentence1: Mollusks are invertebrates such as the common snail. 
Sentence2: Another common snail is the decollate snail.

A: snail
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Q: Sentence1: Most of the hairs, or setae, on insects are sensory and associated with a nerve cell. 
Sentence2: most of the hairs on insects are used to detect stimuli.

A:
Most
****