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.

[Q]: Sentence1: intense heat has a negative impact on an organism. 
Sentence2: intense heat has a negative impact on plants.
[A]: heat


[Q]: Sentence1: Human mating behavior also involves some competition. 
Sentence2: Human mating may lead to aggressive behaviors or displays of aggresion.
[A]: Human


[Q]: Sentence1: Plants are the major producers in terrestrial biomes. 
Sentence2: Green plants are food producers.
[A]:
producers