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: Capillaries are microscopic vessels. 
Sentence2: Lymph is a fluid that leaks out of microscopic vessels into spaces between cells.
[A]: microscopic


[Q]: Sentence1: Organisms that live in marine biomes must be adapted to the salt in the water. 
Sentence2: Most of the water on the planet is salt water in the oceans.
[A]: salt


[Q]: Sentence1: gases from burning coal and oil dissolving in water in the atmosphere causes acid rain. 
Sentence2: Acid rain is harmful rain.
[A]:
acid