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: Water is essential for all life on Earth. 
Sentence2: H2O is needed for all life on Eartth.

A: Earth
****
Q: Sentence1: Warm temperatures have helped plant growth and sizing. 
Sentence2: a greenhouse helps  plant growth.

A: growth
****
Q: Sentence1: sound can be used for communication by animals. 
Sentence2: For mating, communication is between individuals of the same organism.

A:
communication
****