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: rocks interacting with wind over long periods of time causes weathering. 
Sentence2: When a rock undergoes erosion and weathering, it breaks down to form sediments.
weathering

Sentence1: Boiling water can cause burns. 
Sentence2: heating water can cause burns.
water

Sentence1: Organic materials, or living things, are biodegradable. 
Sentence2: Cells are the basic units of the structure and are biodegradable.

biodegradable