This form will generate a set of sample copula sentences, personalised so they will be easier for you to remember. (Use the printer-friendly tab for a nicer printout.) I suggest you read these sentences out loud every day for a week or so, and then keep this page handy for future reference. Any time you are confused about how to form a particular copula sentence, you'll be able to find a similar example here that you can modify by replacing the nouns as needed.

I want sample sentences about a named who is also a(n)

Sin spásaire. That's a astronaut.
Is spásaire [é] an dalta. The student is a astronaut.
Is spásaire Seán. Seán is a astronaut.
Is spásaire é. He is a astronaut.
An spásaire é? Is ea (sea).

Cad í an fadhb? What is the problem?
an spásaire? Is é an dalta an spásaire. Who is the astronaut? The student is the astronaut.
an dalta? Is é an spásaire an dalta. Who is the student? The astronaut is the student.
Note: The subject goes first, then the predicate.

Is é an spásaire é. He is the astronaut.
(The first "é" is just a proleptic pronoun. "The astronaut" is the predicate, and the second "é" is the subject, so it is required.)
? Who is he?
tusa? Who are you?
Is mise an spásaire. I am the astronaut.
Is mise Seán. I'm Seán
Seo é Seán. This is Seán. / Here is Seán.
Is é Seán an spásaire. Seán is the astronaut. / The astronaut is Seán.

Restructuring a sentence to avoid an indefinite subject:
*Is duine spásaire. A astronaut is a person.
- Better (Ulster): Duine atá sa spásaire.
- Better (Other dialects): Is duine é an spásaire. -or- Duine is ea an spásaire.

Split predicate
Is spásaire é a bhfuil a lán eolais faoin chopail aige. He's a astronaut who knows a lot about the copula.