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: All chemical reactions require activation energy to get started. 
Sentence2: Catalysts lower the activation energy.
[A]: activation


[Q]: Sentence1: Plants that shed their leaves seasonally each year are called deciduous plants. 
Sentence2: vines shed their leaves seasonally each year.
[A]: each


[Q]: Sentence1: Most salamanders use their sense of smell to find a mate. 
Sentence2: An odor, by definition, is a sensation, stimulation or perception of the sense of smell.
[A]:
sense