Used to express 'not at all' or 'completely' in negative sentences.
ぜんぜん + Verb-negative, ぜんぜん + い-Adjective-negative, ぜんぜん + な-Adjective-negative, ぜんぜん + Noun + じゃない
Long explanation:
The ぜんぜん grammar point is used to emphasize a negative statement and can be translated as 'not at all' or 'completely'. It is commonly used with negative verbs or negative forms of adjectives. ぜんぜん is placed before the verb or adjective.