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.

Input: Consider Input: Sentence1: Bees feed on nectar and pollen. 
Sentence2: Plant reproduction often requires bees and nectar.

Output: Bees


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

Output: Interest


Input: Consider Input: Sentence1: uneven heating of the Earth 's surface cause wind. 
Sentence2: uneven heating of the Earth's surface causes chinooks.


Output: Earth