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: Average vehicle speed rises by only 0.3 miles per hour. 
Sentence2: a speedometer measures miles per hour.

Ex Output:
hour


Ex Input:
Sentence1: dew is formed when water vapor condenses over night. 
Sentence2: When water vapor condenses overnight, the temperature has reached the dew point.

Ex Output:
condenses


Ex Input:
Sentence1: Roots have primary and secondary meristems for growth in length and width. 
Sentence2: Growth occurs in meristems.

Ex Output:

growth