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: Mammals depend on the vegetation for food and shelter. 
Sentence2: Mammals are Heterotrophs.
Mammals

Sentence1: Most bryophytes are small. 
Sentence2: Most in the same group as mosses are small.
small

Sentence1: Mollusks are invertebrates such as the common snail. 
Sentence2: Another common snail is the decollate snail.

snail