Demonstratives in Irish

Overview

Demonstratives are the words for "this," "that," and "that over there." In Irish, the three demonstrative words are seo (this), sin (that), and siúd or úd (that over there). Unlike English, where demonstratives come before the noun, Irish places them after the noun, and the noun must have the definite article an.

The basic structure is an + noun + seo/sin/siúd: an fear seo (this man), an teach sin (that house), an leabhar siúd (that book over there). This three-way distinction based on distance — near the speaker, near the listener, and far from both — is a feature that English has largely lost (English once had "this/that/yon").

Demonstratives can also stand alone as pronouns: Cad é seo? (What is this?), Is maith liom an ceann sin (I like that one). They are among the most frequently used words in conversation, so mastering them early will greatly help your Irish.

How It Works

The Three Demonstratives

Irish	English	Distance
seo	this / these	near speaker
sin	that / those	near listener or recently mentioned
siúd / úd	that over there	far from both

With Nouns (requires definite article)

Irish	English
an fear seo	this man
an bhean sin	that woman
an teach siúd	that house over there
na leabhair seo	these books
na daoine sin	those people

As Pronouns

Irish	English
Cad é seo?	What is this?
Cad é sin?	What is that?
Is maith liom seo.	I like this.
Tabhair dom an ceann sin.	Give me that one.

With the Copula

Irish	English
Seo é mo theach.	This is my house.
Sin í mo dheirfiúr.	That is my sister.
Is é seo an áit.	This is the place.

Examples in Context

Irish	English	Note
an leabhar seo	this book	Article + noun + seo
an teach sin	that house	Article + noun + sin
Cad é seo?	What is this?	Pronoun use
Is maith liom an ceann sin.	I like that one.	"ceann" = one (thing)
Seo é mo chara.	This is my friend.	Introduction
Sin í an fhadhb.	That is the problem.	Feminine noun with "í"
An bhfuil na rudaí seo agat?	Do you have these things?	Plural + demonstrative
Cé hé sin?	Who is that?	Asking about a person
An leabhar seo nó an ceann sin?	This book or that one?	Comparing two items
Ná déan sin!	Don't do that!	Pronoun in command

Common Mistakes

Forgetting the definite article

• Wrong: fear seo
• Right: an fear seo
• Why: When used with a noun, demonstratives require the definite article an (or na for plural) before the noun.

Placing the demonstrative before the noun

• Wrong: seo an fear
• Right: an fear seo
• Why: In Irish, the demonstrative follows the noun, not precedes it as in English.

Confusing seo/sin in introductions

• Wrong: Seo é sin (mixing both)
• Right: Seo é Seán. (This is Seán.) / Sin í Máire. (That is Máire.)
• Why: Use seo for introducing someone present and sin for referring to someone or something already mentioned.

Practice Tips

1. Point to objects around you and practice the pattern: an rud seo (this thing), an rud sin (that thing), an rud siúd (that thing over there).
2. Practice introductions using Seo é/í... and Sin é/í... with people or photos.

Related Concepts

• The Definite Article — the article required when using demonstratives with nouns