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

Sentence1: if an object is made of a material then that object has the properties of that material. 
Sentence2: If an object is made of a drug, then that object has the properties of that drug.
made

Sentence1: a light bulb is used for seeing in the dark. 
Sentence2: Light bulbs are used to avoid stumbling around in basements.

bulb