We often use the structure appear to be, especially before a noun, [subject + appear (to be) + adjective”]
He appeared very angry. (NOT . . . very angrily.)
[subject + appear to be + noun] She appears to be a very religious person.
[ subject (+ adverb) + appear (+ adverb/adverb phrase)]
A face suddenly appeared at the window.
Mary appeared unexpectedly this morning and asked me for some money.