Necessity sentences express that something must be done. It can be used in affirmative sentences, but also as an order. In the case with orders, they’re often interchangeable with the imperative.

• Minun täytyy opiskella enemmän. “I have to study more.”
• Kaisan pitää imuroida. “Kaisa has to vacuum.”
• Meidän on pakko lähteä. “We really have to leave.”

1. Genitive + täytyy + basic form

When you want to say you have to do something or must do something, you have to use a special sentence construction in Finnish. This construction requires the subject of the sentence to be inflected in the genitive case.

The following table contains the personal pronouns and their genitive form. In addition to personaly pronouns (minun täytyy “I have to”), also nouns (lapsen täytyy “the child has to”) and names (Lassen täytyy “Lasse has to”) will be inflected in the genitive case.

2. Täytyy, pitää, on pakko

There are several verbs to express necessity. Most common are “minun täytyy“, “minun pitää” and “minun on pakko“. All three require the subject to be inflected in the genitive case (minä > minun). The following three sentences all mean “you have to leave”:

The verbs täytyä and pitää are interchangeable in meaning. In Finnish language learning books and website, the verb täytyä is used especially often. In spoken language, however, pitää is often more common. It’s likely that course books focus more on “minun täytyy” because the verb pitää has so many other meanings and functions in Finnish.

Historically, the verb täytyä was used especially in Western and Tavastian dialects. The verb pitää in the same meaning is Eastern, but has also been used in the West. In contrast, täytyä was rare in any other place than the West.

There are also other verbs and constructions you can use, which you can find at the end of this article. If you’re a beginner, you can ignore these other ways for now.

3. Basic form of the main verb

The verb of necessity sentences (täytyy, pitää, on pakko) will not be conjugated. This tendency for the verb not to agree with the number of the subject is called incongruence.

In addition, the second verb (ie. the one that expresses what you are required to do) will always appear in its infinitive form.

4. Negative necessity sentences

Just like in affirmative sentences, the necessity verb (täytyy, pitää) will stay the same in every person; you don’t conjugate the verb. Notice that — regardless of the verb used in the affirmative sentence — the negative version will always have “ei tarvitse“!

Genitive + ei tarvitse + infinitive

This is how we get pairs such as “You have to study.” (Sinun täytyy opiskella) and “You don’t have to study.” (Sinun ei tarvitse opiskella).

I would recommend not trying to use the forms “ei täydy” and “ei pidä“. While these forms are possible, they’re rarely used, and usually in a slightly different meaning. You’re better off sticking to “ei tarvitse” with täytyy and pitää.

If you’re looking to express that someone isn’t allowed to do something, you utilise the verb saada for this. This isn’t a necessity sentence because the subject is sinä rather than sinun and the verb is conjugated (en saa, et saa). The verb saada in this context means “to be allowed to, to have permission”. For example: “Äiti sanoi, että saan tulla leikkimään.” means “Mother said that I can come play”. When made negative, it expresses that you are not allowed to do something.

5. The Object of a Necessity Sentence

Objects in Finnish sentences often appear in the genitive or partitive case. If you’re a total beginner, this might be new information for you. The object rules are pretty complicated: they’re one of those things you’ll be struggling with for a very long time in your studies. Don’t worry too much about the following section if you’re still a beginner: it will start to make sense later.

5.1. Affirmative Sentences

The total object of an affirmative täytyy-sentence will be in its basic form (the nominative case).

Objects can also appear in the partitive. When using a necessity sentence construction, these objects will remain in the partitive (see the last example in the table below). There are multiple reasons to have a partitive object. I’m listing some sentences which have a mass nouns as their object (#1) and sentences with a partitive verb (#2).

5.2. Negative Sentences

A negative sentence with an object will always require the partitive case.

6. Different Ways to Express Necessity

6.1. Necessity Sentences in Spoken Language

In spoken language there are several variations when it comes to the verb of the sentence. Instead of “minun täytyy” it is possible to say “mun täytyy” or “mun tarttee“.

“Minun ei tarvitse” could also be “mun ei tarvitse“, “mun ei tarvii“, “mun ei tarvi” or “mun ei tartte” depending on the dialect of the person speaking. I have a separate article about necessity sentences in colloquial Finnish here.

6.2. Other Ways to Express Necessity

The three most common types of necessity sentences contain täytyy, pitää and on pakko. The following table contains other ways in which you can also express necessity. These verbs differ in how intense the necessity is.

More on the same topic:

If you’ve already mastered basic täytyy-sentences, you could take a closer look at one of these articles:

Related posts:

Minulla on – Possession (Having Something) – Finnish The Sinä-Passive and Other Generic Sentences Expressing Necessity with a Passive Participle – On Mentävä, On Odotettava Finnish Sentence Types Expressing Change: Tuloslause vs. Muutoslause