Incessant
Part of speech: adjective
Definition: Without pause or stop; not ending, especially to the point of annoyance.
Example sentence: I defied the machinery to make me its slave. Its incessant discords could not drown the music of my thoughts if I would let them fly high enough.
Endless
Part of speech: adjective
Definition: having no endextending indefinitely
Example sentence: If you want to build a ship, don't drum up people to collect wood and don't assign them tasks and work, but rather teach them to long for the endless immensity of the sea.