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.

[EX Q]: Sentence1: Blood is a fluid connective tissue. 
Sentence2: A fluid connective tissue carries oxygen to the brain.
[EX A]: connective

[EX Q]: Sentence1: Animals behave in a variety of ways which enhance their chances of survival and reproduction. 
Sentence2: Animals learn to behave to increase chances of survival.
[EX A]: behave

[EX Q]: Sentence1: adding salt to a solid decreases the freezing point of that solid. 
Sentence2: adding salt to ice decreases the freezing point of that ice.
[EX A]:
adding