intermediate
Adds a second, often bigger point on top of the first.
Usage
Nouns: Noun + 뿐만 아니라 (가격뿐만 아니라).
Verbs / Adjectives: Add the modifier first — (으)ㄹ 뿐만 아니라 (싸ㄹ 뿐만 아니라, 맛있을 뿐만 아니라).
The second clause usually carries 도: A뿐만 아니라 B도.
Example:
한국어뿐만 아니라 중국어도 해요. (I speak not only Korean but also Chinese).
Nuance
The weight falls on the second item — it is the more surprising or more important one.
뿐 on its own means "only" and closes things off (이것뿐이에요 = that's all there is). 뿐만 아니라 does the opposite and opens things up.
In speech people often shorten it to 뿐 아니라; the meaning is identical.
In Context
이 식당은 음식뿐만 아니라 서비스도 좋아요.
This restaurant has good food and good service too.
그는 똑똑할 뿐만 아니라 성실해요.
He is not only smart but also diligent.
비뿐만 아니라 바람도 심해요.
Not only is it raining, the wind is bad too.