An exclamatory sentence is a sentence you would be likely to "scream" in the real life: it expressed a great emotion, such as anger or surprise. An exclamatory sentence typically ends with an exclamation mark.
The subject is Cynthia, the verb is “is”, the predicate noun is singer, and the adjective is excellent. Hope this helps!
TV show: Stanford Pines
Book: Alex Hirsch and Rob Renzetti