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.

Q: Sentence1: Scyphozoans are the next group of Cnidarians, and they are the familiar jellyfish. 
Sentence2: Scyphozoans are aquatic organisms.

A: Scyphozoans
****
Q: Sentence1: Amphibians are the first true tetrapods, or vertebrates with four limbs. 
Sentence2: Frogs are classified as amphibians.

A: Amphibians
****
Q: Sentence1: cycles of freezing and thawing water cause ice wedging. 
Sentence2: An ordinary ice road is therefore severely damaged by cracks induced by the traffic.

A:
ice
****