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: freezing means changing from a liquid into a solid by reducing heat energy. 
Sentence2: Water freezes into ice when cooled.

SOLUTION: freezing

PROBLEM: Sentence1: Cows are social animals. 
Sentence2: when a cow moves, chemical energy is converted to mechanical energy.

SOLUTION: Cows

PROBLEM: Sentence1: Males are very aggressive during mating season. 
Sentence2: Males can intend to cause harm or pain during their mating season.

SOLUTION:
Males