It is common in informal speech and writing but is neither rare nor wrong in serious discourse. Often they make the meaning of the adverb or adjective stronger, or more intense We can use pretty as an adverb, before an adjective or another adverb, meaning ‘quite, but not extremely’
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… that's a pretty hat you're wearing
The sofa was covered in very pretty flowery material
She's got such a pretty daughter She looked pretty in a simple cotton dress. Pleasing or attractive to the eye, as by delicacy or gracefulness. See examples of pretty used in a sentence.
Pretty (comparative prettier, superlative prettiest) pleasant to the sight or other senses Attractive, especially of women or children [from 15th c.] coordinate term, near synonym quotations coordinate term If you describe someone as pretty, you mean that they are attractive
She's a very charming and very pretty girl.
Answer pretty, fairly, really, very, and quite are placed directly in front of adjectives or adverbs to add to their meaning
