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.

[Q]: Sentence1: erosion causes a river to become deeper and wider. 
Sentence2: On the contrary, the NILE is the longest river in Africa.
[A]: river


[Q]: Sentence1: when a river floods , that river deposits soil in flood plains. 
Sentence2: when a river floods, it deposits soil in generally marshy areas.
[A]: deposits


[Q]: Sentence1: Menopause occurs when menstruation stops occurring, usually in middle adulthood. 
Sentence2: A woman's reproductive years usually ends in middle adulthood.
[A]:
adulthood


