HSK 4
不是...而是... (búshì...érshì) in Chinese
不是...而是... rejects or corrects one description and replaces it with another. 不是 introduces the rejected alternative, while 而是 introduces the intended one. The two parts should contrast comparable roles, such as two causes, identities, actions, or qualities. A subject shared by both parts normally appears before 不是.
STRUCTURE
Subject + 不是 + A, 而是 + B (contrast)
When to use 不是…而是… — and when not
Use it when
- To correct an identity: 他不是老师，而是医生。
- To replace one cause with another: 我迟到不是因为起晚了，而是因为地铁停了。
- To contrast two actions by one subject: 她不是不想去，而是没有时间。
Don't use it when
- For a simple contrast where the first statement remains true; use 但是 or 可是 instead.
- Do not stack 不是 and 而是 before the rejected alternative.
- Do not force two unrelated grammatical roles into the A and B slots; the correction needs a parallel contrast.
Right vs. wrong
他不是而是老师，是医生。
他不是老师，而是医生。
Both markers are stacked before the rejected alternative
不是 must introduce the rejected identity 老师, and 而是 must introduce the replacement 医生.
这本书不是我买的，朋友而是送给我的。
这本书不是我买的，而是朋友送给我的。
而是 is placed after the subject of its replacement clause
而是 introduces the entire replacement clause 朋友送给我的, so it belongs before that clause's subject.
Examples
他不是老师，而是医生。
Tā bú shì lǎoshī, ér shì yīshēng.
He is not a teacher but a doctor.
我迟到不是因为起晚了，而是因为地铁停了。
Wǒ chídào bú shì yīnwèi qǐ wǎn le, ér shì yīnwèi dìtiě tíng le.
I was late not because I got up late, but because the subway stopped.
她不是不想去，而是没有时间。
Tā bú shì bù xiǎng qù, ér shì méiyǒu shíjiān.
It is not that she does not want to go; she has no time.
Common mistakes
他不是而是老师，是医生。
Tā bú shì ér shì lǎoshī, shì yīshēng.
Separate the markers around the alternatives: 他不是老师，而是医生。
这本书不是我买的，朋友而是送给我的。
Zhè běn shū bú shì wǒ mǎi de, péngyou ér shì sòng gěi wǒ de.
Place 而是 before the replacement clause: 而是朋友送给我的。
Think you've got it?
Write your own 不是…而是… sentence and check that grammar point first.
不是...而是... (búshì...érshì) FAQ
What is the difference between 不是...而是... and 虽然...但是...?
不是...而是... rejects A and replaces it with B. 虽然...但是... accepts the first fact and introduces a contrasting result, so both facts remain true.
Can 不是...而是... contrast reasons?
Yes. A common form is 不是因为 A，而是因为 B, which rejects one explanation and supplies another. Keep the two reason phrases parallel.