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: when a river floods , that river deposits soil in flood plains. 
Sentence2: Hurricanes can cause local flooding, flash flooding, or coastal flooding.
[A]: flood


[Q]: Sentence1: Basically, heat is energy. 
Sentence2: Head hair is especially important in preventing energy loss from the body.
[A]: energy


[Q]: Sentence1: producing thrust causes something to move. 
Sentence2: Although electric rockets are efficient, their thrust is low.
[A]:
thrust