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: Some trees are maples. 
Sentence2: planting maples has a positive impact on an ecosystem.
[A]: maples


[Q]: Sentence1: killing microorganisms in food can be used to extend the shelf life of that food. 
Sentence2: Cooking can be used to extend the shelf life of food.
[A]: be


[Q]: Sentence1: safety goggles are used for protecting the eyes during experiments. 
Sentence2: safety goggles are used to protect the eyes from dangerous things.
[A]:
eyes