In my family I'm the only one who isn't French.
Is mise amháin .......i mo mhuintir....

I dteaghlach s'againne is mé an t-aon duine nach Francach é(Masc)/ í (fem)

I'm not sure about the necessity of "é" at the end of the sentence. Sounds unnecessary, but I'm not sure either of the sentence without it. Actually you don't often use "who isn't X" at the end of a sentence, so I've no sentence in mind that would tell me if it's wrong or not...

Ins an teaghlach s'agamsa is mise an t-aon duine amháin nach Francach.
In mo theaghlach is mise an t-aon duine amháin nach Francach.
Is mise an t-aon duine amháin in mo theaghlach, nach Francach.

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Because it's so complex, this is a good example to anayse in detail; it may help others. For the moment, let's just focus on the grammar, and later we can worry about whether or not the sentence turns out a little awkward to say. My mental process goes something like this: What is the fundamental core of the sentence? It's:

I am the only person.

All the other stuff in the setence is just a modifier for "person". This sentence is equating two things (I = person), so it's an identification sentence requiring the copula. Let's consult the WUCT


Normally we would use "mise" for "I" in this kind of sentence, so the subject is emphatic, and it comes first.

Is mise an t-aon duine amháin. I am the only person.

Now we can think about the "who isn't French" part. This is a relative clause, but before we worry about that, let's consider how we would say it as an independent sentence. I'm using Francach as an adjective(French) rather than as a noun (French person) so that we don't have to use the copula in this part. Note that An Fear Gaelach and Lughaidh are using Francach as a noun, which is why their sentences are different!

Níl __ Francach. __ isn't French.

The __ is a placeholder for an t-aon duine amháin, or sé if you prefer. So now we need to convert "__ isn't French" into "...who isn't French" This is a direct reative clause, because who refers back to the subject. But for a negative relative clause, it doesn't even matter whether the clause is direct or indirect; as you'll see from the chart in my discussion of the relative clause, we eclipse in both cases.

...nach bhfuil Francach ...who isn't French

And as Franc suggested, we can use i mo mhuintir for "in my (extended) family". So putting it all together, we have:

Is mise an t-aon duine amháin nach bhfuil Francach, i mo mhuintir. I am the only person in my family who isn't French.

Or we can make it flow a bit better:

I mo mhintir, is mise an t-aon duine amháin nach bhfuil Francach. In my family, I am the only person who isn't French.

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Go raibh maith agaibh

'nach bhfuil Francach' = TSF. Francach/Eireannach etc in this context are nouns. It has to be 'nach Francach [é]. And 'i mo mhuintir' [assuming the extended family is meant] sounds strange to me. I'd use 'de mo mhuintir'.

I agree with Errigal.

Can't "Francach" and "Éireannach" be either nouns or adjectives? I would think:

Níl mé Francach: I am not French.

Ní Francach mé: I am not [a] French [person].

Redwolf

Yes, you're right (although Níl mé Francach just sounds a bit odd/unnatural to me). Lughaidh's suggestion doesn't fall into either camp. ...nach Francach certainly isn't a turn of phrase I've heard. It neither equates to Níl mé Francach nor Ní Francach mé.

The subject is before "nach", that's why you may not need to add "é" or whatever at the end.
Look at the sentences with the superlatives:
Is é an duine is deise, he is the nicest person.
Normally you don't say "Is é an duine ar deise é" (which corresponds to your sentence with "nach Francach é", in a grammatical point of view).

When talking about people, I don't think you can say "Tá X Francach". You wouldn't say "Tá mé Francach" but only "Is Francach mé", in my opinion (ie. you don't say "I am French" but "I am a Frenchman" in Irish).

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