Modal Expressions in Irish

Overview

Modal expressions allow you to talk about ability, obligation, desire, and necessity — "I can," "I must," "I want to." In Irish, these concepts are not expressed with simple auxiliary verbs as in English. Instead, they use combinations of the copula, prepositions, and prepositional pronouns, which makes them a natural extension of the grammar you are already learning at the A1 level.

The most common modal expressions are is féidir le (can/is able to), caithfidh (must), ba mhaith le (would like), and ní mór do (must/need to). Each of these follows its own pattern, but they all rely on prepositional pronouns to indicate who can, must, or wants to do something.

These expressions are among the most useful in daily conversation — asking permission, expressing needs, and stating what you would like are fundamental communicative tasks.

How It Works

Expression	Meaning	Structure
Is féidir le...	can / is able to	Is féidir liom + VN (I can...)
Ní féidir le...	cannot	Ní féidir liom + VN (I cannot...)
Caithfidh...	must / have to	Caithfidh mé + VN (I must...)
Ba mhaith le...	would like	Ba mhaith liom + noun/VN
Ní mór do...	must / need to	Ní mór dom + VN (I need to...)
Is ceart do...	should	Is ceart dom + VN (I should...)

VN = verbal noun (the infinitive-like form)

Examples in Context

Irish	English	Note
Is féidir liom snámh.	I can swim.	Ability — liom = with me
Caithfidh mé dul.	I must go.	Obligation
Ba mhaith liom caife.	I would like coffee.	Polite request
Ní féidir liom teacht.	I can't come.	Negative ability
Ní mór dom staidéar a dhéanamh.	I need to study.	Necessity
An féidir leat cabhrú liom?	Can you help me?	Question — ability
Caithfidh tú éisteacht.	You must listen.	Obligation — 2nd person
Ba mhaith léi dul abhaile.	She would like to go home.	3rd person feminine
Is ceart duit é a dhéanamh.	You should do it.	Advice
Ní chaithfidh tú fanacht.	You don't have to stay.	Negative obligation

Common Mistakes

Using the wrong prepositional pronoun with is féidir

• Wrong: Is féidir mé snámh
• Right: Is féidir liom snámh
• Why: "Is féidir le" uses the preposition le (with). You must use the correct prepositional pronoun: liom, leat, leis, léi, etc.

Confusing caithfidh (must) with is féidir (can)

• Wrong: Caithfidh mé snámh when you mean "I can swim"
• Right: Is féidir liom snámh
• Why: Caithfidh expresses obligation (must), while is féidir expresses ability (can). Choose based on meaning.

Forgetting the verbal noun after modal expressions

• Wrong: Ba mhaith liom téigh abhaile
• Right: Ba mhaith liom dul abhaile
• Why: After modal expressions, use the verbal noun (dul), not the verb root (téigh).

Practice Tips

1. Practice the four core modals with everyday activities: "Is féidir liom Gaeilge a labhairt" (I can speak Irish), "Caithfidh mé dul ag obair" (I must go to work), "Ba mhaith liom dul ag siúl" (I'd like to go walking).
2. Focus on the prepositional pronoun patterns — liom/leat/leis with le, and dom/duit/dó with do — since these recur across many modal constructions.

Related Concepts

• Prepositional Pronouns — the foundation for all modal expressions