In Finnish, you can make questions in two ways: by using a question word like mikä, miksi and kuka, and by using the -ko/kö suffix. This is how we create a kysymyslause (a “question sentence”, ie. an interrogative clause).

This article tells you more about the types of kysymyslause Finnish has! You can find an overview of all the different sentence types (lausetyypit) in Finnish on this page.

1. Questions with a question word

The first type of interrogative sentences uses an interrogative pronoun ie. a question word (kysymyssana). This word will appear at the beginning of the sentence. The rest of the sentence will have the same word order as the normal, affirmative sentence would have.

I have another, longer article that goes through all the question words in more detail here. I also go over how questions are typically formed in spoken Finnish here.

2. Questions with the -ko/kö suffix – YES/NO questions

The second interrogative sentence type is the Finnish equivalent of “Do you?”, “Does he?”, “Are they?” and “Will you?” sentences. It’s very common to start these sentences with the verb of the sentence, but almost any word can get the ko/kö suffix. This suffix creates questions that can be answered with “yes” or “no”.

2.1. KO or KÖ?

In order to know whether to add –ko or –kö as the suffix, you need to know about vowel harmony (vokaaliharmonia in Finnish). Words which have an A, O or U will always get -ko. Words without A, O and U will get -kö.

2.2. KO/KÖ added to the verb

When adding KO/KÖ to the verb, you place the verb at the beginning of the sentence and follow it up with the subject.

Note that we can drop the pronouns minä, sinä, me and te from both regular sentences and question sentences! In other words, you can also ask “Syötkö kotona?” and “Haluatteko teetä?“. However, sentences with hän and he must have the pronoun.

2.2. KO/KÖ added to the negative verb

We can also turn negative sentences into questions by adding the suffix KO/KÖ to the negative verb form. For example, “Enkö minä ole oikeassa?” means “Am I not right?” and “Eikö hän tule?” means “Doesn’t he come?”.

2.3. KO/KÖ added to other words

By adding KO/KÖ to another word besides the verb, we can change the focus of the question.

Another example:

There are of course limits to which words can be put into question using the suffix -kO. For example, conjunctions like mutta and kun won’t work with this suffix. In addition, while there is the theoretical possibility to add the suffix, it can be difficult to find a context where these sentences are actually useful. It’s by far the most common to add the suffix to the verb in the sentence.

3. Subordinate interrogative clauses – Epäsuora kysymyslause

We can also make more complex sentences, consisting of multiple clauses. It is, for example, possible to make sentences with a subordinate clause containing a question (epäsuora kysymyslause). The first part of the full sentence can either also be a question, or just be a regular sentence. You will add a question mark to the complete sentence when the main clause (ie. the first part) is a question. If not, just use a full stop.

Note how in English, you will use “if” rather than a KO/KÖ question. You cannot use “jos” in Finnish in these situations!

4. Word order in question sentences

An interrogative sentence will start with either a question word such as missä (where), or with a word with the KO/KÖ suffix. The rest of the sentence is generally similar to what the sentence would look like as a väitelause.

One question regarding word order in question that comes up fairly regularly is where to put the verb olla in questions. In general, you will put the “on” at the end of the sentence. This creates a question that assumes the existence of the thing and asks about its location (ie. surely there is a coffee shop nearby, but I want to know where). In contrast, when putting “on” right after the question word, these questions imply uncertainty as to whether there is any nearby at all.

I find it is hard for beginning learners of Finnish to grasp the difference in the beginning of their studies. I think – in general – you will be asking where something is while assuming that it exists. Thus, I suppose you could consider sentences with the “on” at the end of the question as the default you stick to until you get more of a feel of how word order works in Finnish.

5. Spoken language questions

Note that spoken language question sentences have their own rules in some cases. I have a whole article about asking questions in colloquial Finnish that you should check out separately.

Tiedätkö nyt, millainen kysymyslause voi olla? Let me know if I failed to mention something vital!

Related posts:

Finnish Question Words – Interrogative Pronouns How to Say Yes and No in Finnish – Kyllä ja Ei Existential Sentences – Jossain on jotain Mones Monesko Monentena – How does mones work?