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: Erosion of rock makes nutrients available. 
Sentence2: rain causes nutrients to be available.
[A]: nutrients


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


[Q]: Sentence1: when a hemisphere is tilted away from the sun , that hemisphere receives less direct sunlight. 
Sentence2: When the axis is pointed toward the sun, more light falls on that hemisphere.
[A]:
sun