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: waxy leaves are used for storing water by some plants. 
Sentence2: waxy leaves are used for water conservation by some plants.
[A]: leaves


[Q]: Sentence1: Dromaeosaurs are part of the theropod group of dinosaurs. 
Sentence2: Birds evolved from a group of bipedal dinosaurs that included Dromaeosaurs.
[A]: Dromaeosaurs


[Q]: Sentence1: Fractures heal when osteoclasts form new bone. 
Sentence2: Bone is a living tissue.
[A]:
bone