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: healing requires rest. 
Sentence2: Healing and cell regeneration follows.

SOLUTION: healing

PROBLEM: Sentence1: a flashlight converts chemical energy into light energy. 
Sentence2: Chemical energy converted to light energy requires batteries.

SOLUTION: chemical

PROBLEM: Sentence1: Adolescence begins with puberty. 
Sentence2: Growth is faster in infancy than in adolescence.

SOLUTION:
Adolescence