instruction:
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.
question:
Sentence1: Electrical currents cause magnetic fields. 
Sentence2: Electrical currents can cause objects to repel each other.
answer:
Electrical


question:
Sentence1: a polar bear requires a cold environment. 
Sentence2: polar bears live where there are fewer animals.
answer:
bear


question:
Sentence1: Humans depend upon the life-support systems provided by the oceans. 
Sentence2: coral reefs provide support for humans.
answer:

Humans