As an adjective:
* The artist's vision was singular, unlike anything else on the market.
* The museum housed a singular collection of medieval artifacts.
* Her beauty was singular and captivating.
* The detective focused on a singular piece of evidence that proved the suspect's guilt.
As a noun:
* The singular of "sheep" is "sheep."
* The word "data" is usually treated as a singular, even though it refers to multiple pieces of information.
* The grammar rule is: use a singular verb with a singular noun.
In other contexts:
* The hero's journey is a singular theme found in many stories.
* Her love for him was a singular and powerful force in her life.
* The author's unique writing style gave the book a singular charm.
Remember that "singular" can have different meanings depending on the context. Be sure to consider the intended meaning when using the word in your own writing.