无不 / 莫不【wúbù / mòbù】

无不 and 莫不 put two negatives together – "there is no one who does not" – to say that everyone or everything in a group does something. The group comes first, and 无不 or 莫不 goes before the verb.

Stronger than 都

无不 says what 都 says and adds weight: no exception was found. It suits essays and reports, often with a 的 phrase as the group.

无一不 "not one that doesn't" is stronger still.

The 不 is already there

无不 contains its own 不. Adding another negative turns the sentence upside down.

• × 大家无不不同意 → 大家都不同意
• × 大家无不没来 → 大家都没来

无不 or 莫不

The two mean the same; 莫不 is a little more literary. 莫不是 is a different word – a spoken "could it be that", like 莫非.