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: Damage is intensified by moisture stress during drought. 
Sentence2: low amounts of rainfall intensify damage during drought.

SOLUTION: Damage

PROBLEM: Sentence1: when a gas in an open container evaporates , that gas spreads out into the air. 
Sentence2: If you place gas in an open box it will evaporate and spread out into the air.

SOLUTION: gas

PROBLEM: Sentence1: Mammals took advantage of the extinction of the dinosaurs. 
Sentence2: Mammals took advantage of the extinction of giant lizards.

SOLUTION:
Mammals