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: Similarly, stars are referred to as suns, but our star is the Sun. 
Sentence2: our star causes water to evaporate more quickly by adding heat.
[A]: our


[Q]: Sentence1: Ground tissue makes up most of the interior of a plant. 
Sentence2: ground tissue makes up most of the interior of a dandelion.
[A]: Ground


[Q]: Sentence1: when water freezes , that water expands. 
Sentence2: Upon further cooling to 32 degrees Fahrenheit, water expands as it turns to ice.
[A]:
expands