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: Female monotremes lack a uterus and vagina. 
Sentence2: Babies are normally delivered from the uterus through the vagina.
[EX A]: uterus

[EX Q]: Sentence1: Climate refers to weather over a long period of time. 
Sentence2: weather is generally described in terms of temperature and moisture.
[EX A]: long

[EX Q]: Sentence1: Smog also contains particulates. 
Sentence2: Smog contains very small or liquid particles in the air.
[EX A]:
Smog