Compliments And Flattery Expressions

adjective A word that describes or modifies a noun or pronoun, in this case 'bad-looking' describes the noun

adverb A word that modifies a verb, adjective, or other adverb, in this case 'not' modifies the adjective 'bad-looking'

• The new employee is not bad-looking and seems quite professional.
• I saw that guy at the party last night, he's not bad-looking at all.
• That girl over there is not bad-looking, huh?
• The painting may not be bad-looking, but it lacks depth and emotion.