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: friction causes the temperature of an object to increase. 
Sentence2: internal combustion engines get hot.
temperature

Sentence1: Soil Erosion Soil erosion is a natural process. 
Sentence2: wind and rain is a natural process.
natural

Sentence1: Many antibiotics are derived from fungi. 
Sentence2: bladder infections can be treated with fungi.

fungi