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 Input:
Sentence1: Mangoes are propagated vegetatively and by seeds. 
Sentence2: animals propagate mangoes.

Ex Output:
Mangoes


Ex Input:
Sentence1: Similarly, stars are referred to as suns, but our star is the Sun. 
Sentence2: our star causes water to evaporate more quickly by adding heat.

Ex Output:
our


Ex Input:
Sentence1: Like frogs, salamanders are amphibians. 
Sentence2: some amphibians use their sense of smell to find a mate.

Ex Output:

amphibians