Breakdown of Hänen täytyy herätä huomenna aikaisin.
hän
he / she
huomenna
tomorrow
herätä
to wake up
täytyä
to have to
Questions & Answers about Hänen täytyy herätä huomenna aikaisin.
Why is the sentence starting with Hänen instead of Hän?
When expressing that someone "must" or "has to" do something using the verb täytyy, the person doing the action must be in the genitive case (the form usually used to show possession). So the basic word hän (he/she) becomes hänen.
Why doesn't the verb täytyy change to match the subject?
Täytyy is a special type of verb in Finnish. In this "must" structure, it is frozen in this exact form. It never changes to match the person, so you will always just use täytyy whether the subject is "I", "you", "we", or "he".
Why do we use the dictionary form herätä (to wake up) here instead of a conjugated form like herää?
When using täytyy, the action verb that follows must always be in the infinitive (its basic dictionary form). Since täytyy handles the grammar for the "must" part of the sentence, herätä simply stays as "to wake up".
Is the word huomenna (tomorrow) related to huomenta as in Hyvää huomenta (Good morning)?
Yes! They both come from the same root word for "morning". Huomenna is specifically the form used to mean "tomorrow" (literally meaning something like "on the next morning").