# Chẳng phải … là gì: rhetorical 'isn't it' in Vietnamese

> Some questions aren't really questions: they mean "surely you know" or "isn't it obvious?".

Source: https://vietnamesebuddy.com/grammar/rhetorical-negative/ · Updated 2026-10-17

**rhetorical 'isn't it'**

Pattern: `Bộ + [person] + không + [verb] + hả? · Chẳng phải + [X] + sao? · [person] + không + [verb] + hay sao?`

Level: B2 (our estimate) · Register: everyday

Typed without accents: chang phai … la gi, hay sao

Saigon: Bộ + [person] + không + [verb] + hả? · Chẳng phải + [X] + sao? | Hà Nội: Chẳng phải + [X] + là gì? · [person] + không + [verb] + hay sao?

Some questions aren't really questions: they mean "surely you know" or "isn't it obvious?". Vietnamese builds them from a negative, or *chẳng phải*, plus a question word at the end.

In Saigon, the everyday version starts with *bộ* and ends with *hả*: *Bộ anh không biết hả?* (You mean you didn't know?) *Bộ* signals surprise, as if the answer should be plain to see.

*Chẳng phải … sao?* (isn't it …? wasn't it …?) reminds someone of something they already know: *Chẳng phải hôm qua chị dặn em rồi sao?* (Didn't I remind you yesterday?)

In Hà Nội, and in writing, you'll also meet *… không … hay sao?* (don't you …, or what?): *Anh không biết hay sao?* And *chẳng phải … là gì?* (if that isn't …, what is?): *Thế chẳng phải lừa đảo là gì?* (If that isn't fraud, what is?)

Tone matters. Said gently, these questions just show surprise. Said sharply, they sound like a telling-off, so take care with older people and strangers.

Compare *chẳng lẽ* (surely not), which doubts something you'd rather not believe: *Chẳng lẽ anh quên rồi?* The forms here push the other way, towards "yes, of course". In writing, *phải chăng* (could it be that) does a calmer version of the same job.

## Examples

- Saigon: Bộ anh không biết hả? Mai nghỉ lễ mà. | Hà Nội: Anh không biết hay sao? Mai được nghỉ lễ mà. — You mean you didn't know? Tomorrow's a public holiday.
- Chẳng phải hôm qua chị dặn em rồi sao? — Didn't I remind you yesterday?
- Saigon: Bán hàng giả như vậy, chẳng phải là lừa đảo sao? | Hà Nội: Bán hàng giả như thế, chẳng phải lừa đảo là gì? — Selling fakes like that, isn't that fraud?
- Saigon: Bộ em không thấy trời sắp mưa hả? | Hà Nội: Em không thấy trời sắp mưa hay sao? — Can't you see it's about to rain?

## Compare

- [Surely not? chẳng lẽ / lẽ nào](https://vietnamesebuddy.com/grammar/chang-le-surely-not/): surely not …?
- [Could it be that …? phải chăng](https://vietnamesebuddy.com/grammar/phai-chang/): is it that …? (written)
- [Who would …? Who wouldn't …? ai mà, ai lại không](https://vietnamesebuddy.com/grammar/ai-ma-rhetorical/): rhetorical who
- [After all, obviously: … (rồi) còn gì](https://vietnamesebuddy.com/grammar/con-gi-obviously/): it's obvious, after all (mild reproach)

Previous in Asking questions: [How could that be! làm sao … được](https://vietnamesebuddy.com/grammar/lam-sao-duoc-rhetorical/)
Next in Asking questions: [Who all, what all: những ai, những gì](https://vietnamesebuddy.com/grammar/nhung-qword-plural/)

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