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: Cancer is a disease in which cells divide out of control. 
Sentence2: Cancer is a disease in which cells grow and divide rapidly.
[A]: Cancer


[Q]: Sentence1: All cells share some of the same structures and basic functions. 
Sentence2: Inside the cell is a structure called the nucleus.
[A]: cells


[Q]: Sentence1: Gasoline is made up of hydrocarbons. 
Sentence2: A car engine converts a fuel of hydrocarbons into motion through combustion.
[A]:
hydrocarbons