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: Visible and invisible light is energy in the form of electromagnetic waves. 
Sentence2: Eyes are used for seeing animals by sensing electromagnetic waves.

Ex Output:
electromagnetic


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

Ex Output:
Mangoes


Ex Input:
Sentence1: erosion causes deposition. 
Sentence2: the movement of soil by water causes deposition.

Ex Output:

causes