TASK DEFINITION: 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.
PROBLEM: Sentence1: Soil Erosion Soil erosion is a natural process. 
Sentence2: wind and rain is a natural process.

SOLUTION: natural

PROBLEM: Sentence1: evaporation can be used for separating a solute from a solvent in a solution. 
Sentence2: Evaporation can be used for segregation a solute from a solvent in a solution.

SOLUTION: a

PROBLEM: Sentence1: cross-pollination increases genetic diversity. 
Sentence2: cross-pollination increases biodiversity.

SOLUTION:
cross-pollination