不是。

When to use

Applies when contradicting a statement or declining an offer.

How it works

Combines the negative particle 不 (bù) with the verb 是 (shì). The tone of 不 changes from 4th to 2nd tone (bú) when followed by another 4th tone character, a common tone sandhi rule.

• 不 (bù): not
• 是 (shì): to be

Notes

A direct negative answer.