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 of soil has a negative impact on the environment. 
Sentence2: erosion of soil has a negative impact on forests.

A: erosion
****
Q: Sentence1: Without light there is no sense of vision. 
Sentence2: Glass causes a sense of vision.

A: sense
****
Q: Sentence1: heavy rains cause flooding. 
Sentence2: flooding can cause landslides.

A:
flooding
****