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: Running water is better able to dissolve oxygen and nutrients than standing water. 
Sentence2: Oxygen and nutrients dissolve easily in rivers.
dissolve

Sentence1: wind is used for producing electricity. 
Sentence2: Winds are caused by pressure differences.
wind

Sentence1: Tidal energy is one of the oldest forms of energy used by humans. 
Sentence2: One of the oldest forms of energy used by humans can be used to produce electricity.

energy