[noun] + ばかりでなく [verb (plain form)] + ばかりでなく [i-adj] + ばかりでなく [na-adj] + な/である + ばかりでなく
Variants:
Second clause often includes も, さらに, or まで.
The grammar structure ばかりでなく means "not only… but also…" and is used to express that something is not limited to just one thing – there is an additional element as well. It emphasizes that both X and Y apply, often with Y being surprising or noteworthy.
ばかりでなく attaches to nouns, verbs, and adjectives:
The second clause typically includes も, さらに, or まで to reinforce the "also" part.
A common variant is ばかりではなく, which adds the particle は for slight emphasis. The meaning is identical.
This pattern is used in both spoken and written Japanese, though it leans slightly toward formal or written contexts. In casual speech, だけでなく or だけじゃなく are more common alternatives with the same meaning.