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: Silica sand is primarily mined from sandstone deposits. 
Sentence2: erosion forms silica sand.
[EX A]: Silica

[EX Q]: Sentence1: Evaporation of sweat uses energy, and the energy comes from body heat. 
Sentence2: Evaporation of sweat uses energy, and the energy comes from exercise.
[EX A]: Evaporation

[EX Q]: Sentence1: insulated material can be used for keeping warm. 
Sentence2: Insulated material is the key to newborn survival.
[EX A]:
insulated