多（么）+ 形容词 + 啊 duō (me) + xíngróngcí + a
多（么）+ 形容词 + 啊（duō (me) + xíngróngcí + a）means “how …!: exclaiming degree with 多/多么…啊”. 多 or 多么 before an adjective, often closed by 啊, forms an exclamation about degree: 'how beautiful. Formation: 多／多么 + 形容词（+ 啊）
how …!: exclaiming degree with 多/多么…啊
HSK2Formation
多／多么 + 形容词（+ 啊）
Explanation
多 or 多么 before an adjective, often closed by 啊, forms an exclamation about degree: 'how beautiful!' 多么 is a bit more emphatic than 多. Separately, 多 + adjective can ask about degree in questions (你多大 'how old are you?').
Examples
Note
多么 is more emphatic than 多. 多 + adjective also asks degree: 你多高?
FAQ
多（么）+ 形容词 + 啊 — what does it mean and how is it used?
how …!: exclaiming degree with 多/多么…啊. 多 or 多么 before an adjective, often closed by 啊, forms an exclamation about degree: 'how beautiful!' 多么 is a bit more emphatic than 多. Separately, 多 + adjective can ask about degree in questions (你多大 'how old are you?').
多（么）+ 形容词 + 啊 — how do you form it?
多／多么 + 形容词（+ 啊）
多（么）+ 形容词 + 啊 — any usage notes?
多么 is more emphatic than 多. 多 + adjective also asks degree: 你多高?