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: the Earth being tilted on its rotating axis causes seasons. 
Sentence2: the planet's orbit and tilt causes seasons.
[A]: seasons


[Q]: Sentence1: igneous rocks are formed from magma cooling. 
Sentence2: magma solidifies into igneous rocks.
[A]: magma


[Q]: Sentence1: Most reptiles have good eyesight and a keen sense of smell. 
Sentence2: some lizards have good eyesight and a keen sense of smell.
[A]:
eyesight