Mary's crestfallen face was surprisingly cute.
The entire team came back looking cresfallen after losing the championshp game.
When Lydia declined his proposal, Henry was crestfallen.
I felt really crestfallen after knowing that i have failed my examinations.
A sentence is a sentence because it has a subject (noun or noun phrase), a predicate ( verb) and punctuation as well as the other parts of speech like pronouns ( she, it him, her, they, them)...