不但⋯⋯而且⋯⋯
bú dàn …… ér qiě ……
Expressing "not only… but also…" with "budan… erqie…"
不但…而且… adds a second, stronger point to the first.
不但 + Clause 1，而且 + Clause 2
How it works
他不但聪明，而且勤劳 — he's not only clever but hard-working too.
Both halves are needed. 还 or 也 often joins the second clause for extra weight: 而且还很便宜.
If the two clauses have different subjects, 不但 moves in front of the first subject.
Examples
tā bú dàn cōng ming, ér qiě qín láo
他不但聪明，而且勤劳。
He's not only clever, but hard-working too.
zhè jiā cān tīng bú dàn hǎo chī, ér qiě hěn pián yi
这家餐厅不但好吃，而且很便宜。
This restaurant is not only tasty but cheap.
bú dàn wǒ qù, ér qiě tā yě qù
不但我去，而且他也去。
Not only am I going, he's going too.