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: Limestone caves displaying stalactites. 
Sentence2: Limestone caves are formed by depositions.

A: Limestone
****
Q: Sentence1: Most bryophytes are small. 
Sentence2: Most in the same group as mosses are small.

A: small
****
Q: Sentence1: Viruses cause many human diseases. 
Sentence2: Influenza virus causes widespread human disease.

A:
Viruses
****