Rhetorical question “..., is it?”
We can ask a rhetorical question using the adverb 莫非 and the structure 难道…吗？
The structure 难道…吗？
We can ask a rhetorical question using the structure 难道…吗 
.
We should state 难道 at the beginning of a sentence or a phrase and use the question particle 吗 at the end.
We should use the predicate in the negative form.
.
We should state 难道 at the beginning of a sentence or a phrase and use the question particle 吗 at the end.
We should use the predicate in the negative form. Pay attention
Rhetorical questions are questions where an answer is not really expected. It is often used to express indignation or astonishment.
Scheme
难道
question
吗?
Examples
难道你不相信我们会赢吗？
Don't you believe we will win?
nándào nǐ bù xiāngxìn wǒmen huì yíng ma
他在骗你，难道你看不出来吗？
He's lying to you, can't you see that?
tā zài piàn nǐ, nándào nǐ kàn bu chūlai ma
The adverb 莫非
We also can use the adverb 莫非 to ask a rhetorical question that expresses surprise. It is used less frequently than 难道.
We should state 莫非 at the beginning of a phrase or sentence.
to ask a rhetorical question that expresses surprise. It is used less frequently than 难道.
We should state 莫非 at the beginning of a phrase or sentence. Pay attention
In sentences with 莫非, we should not use the question particle 吗.
Examples
莫非我错了？
Could it be that I’m wrong?
mòfēi wǒ cuò le
莫非你们觉得我是个骗子？
Do you think I'm a liar?
mòfēi nǐmen juéde wǒ shì ge piànzi
他最近身体不好，莫非真的是老了？
He has not been feeling well lately. Could it be that he is really getting old?
tā zuìjìn shēntǐ bù hǎo, mòfēi zhēn de shì lǎo le
The modal particle 不成
To form a rhetorical question, we can also state 不成 at the end of a sentence.
We usually use it with the following constructions:
难道...不成？
莫非...不成？
at the end of a sentence.
We usually use it with the following constructions:
难道...不成？
莫非...不成？ Examples
难道不许我们说话不成？
Are we not allowed to speak?
nándào bùxǔ wǒmen shuōhuà bùchéng
今天她没来，莫非又生了病不成？
She didn't come today, is she sick again?
jīntiān tā méi lái, mòfēi yòu shēng le bìng bùchéng
我堂堂泰王，还会骗你不成？
I'm the king of Thailand, how could I lie to you?
wǒ tángtáng tài wáng, hái huì piàn nǐ bùchéng