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.

[EX Q]: Sentence1: Energy is the fuel for chemical reactions which run the various systems of the body. 
Sentence2: running requires fuel for chemical reactions which run the various systems of the body.
[EX A]: body

[EX Q]: Sentence1: creating paper requires cutting down trees. 
Sentence2: Trees begin as epiphytes on host trees.
[EX A]: trees

[EX Q]: Sentence1: For example, a fibroid is a tumor, a wart is a tumor, and cancers are tumors. 
Sentence2: Cells that divide uncontrollably may form a fibroid.
[EX A]:
fibroid