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: Introns are regions that do not code for proteins. 
Sentence2: regions that do not code for proteins are removed by RNA splicing.
code

Sentence1: Interest in fossils is worldwide. 
Sentence2: paleontologists study something with worldwide interest.
Interest

Sentence1: Aggressive behavior is often first recognized as bullying behavior. 
Sentence2: Competition can result in bullying.

bullying