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: Viruses are usually considered to be nonliving. 
Sentence2: Viruses are usually acquired from contact with infected animals.

SOLUTION: Viruses

PROBLEM: Sentence1: Most soil nutrients are cations. 
Sentence2: decomposition increases the amount of cations in the soil.

SOLUTION: cations

PROBLEM: Sentence1: Fertilization occurs naturally in the fallopian tubes. 
Sentence2: fertilization is used for reproduction.

SOLUTION:
Fertilization