* "I have a lot of work to do today." (Here, "work" refers to the tasks or duties to be completed.)
* "The artist's work is on display at the museum." (Here, "work" refers to the artist's creations.)
* "The construction work is noisy." (Here, "work" refers to the physical labor being done.)
However, "work" can also be a verb, as in "I work at a bank."
The part of speech depends on the context of the sentence.