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: Lancelet larvae are free-swimming. 
Sentence2: some larvae lack a hardened backbone.

SOLUTION: larvae

PROBLEM: Sentence1: high temperatures can cause an object to combust. 
Sentence2: incineration causes an object to combust.

SOLUTION:
combust