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.

Sentence1: Water erosion has similar consequences as wind erosion. 
Sentence2: exposure to water can cause erosion.
Water

Sentence1: Tree-ring dating the 1700 Cascadia earthquake. 
Sentence2: estimating the age of trees can be used in reviewing earthquake history.
earthquake

Sentence1: condensation is when change from a gas into a liquid by reducing heat energy. 
Sentence2: Condensation is the reverse of vaporization , or change from liquid to gas.

condensation