Learn Finnish: Algoritmi aktivoituu, kun käyttäjä klikkaa linkkiä. - The algorithm becomes active when the user clicks the link.

The suffix -oitua is an automative suffix used to show that something happens by itself or undergoes a process. Here, it attaches to the loanword root aktiiv- to form aktivoitua (to become active). It tells us the algorithm is activating itself, contrasting with the transitive verb aktivoida (to activate something).

If I wanted to say 'The user activates the algorithm,' how would this sentence change?

You would use the transitive verb aktivoida instead of the automative aktivoitua. The sentence would be Käyttäjä aktivoi algoritmin. Notice that algoritmi changes to the genitive-accusative case (algoritmin) because it becomes the total object of the action.

What is the infinitive of klikkaa, and why doesn't the vowel double for the 3rd person singular?

The infinitive is klikata, which is a Type 4 verb. To find the present stem, you remove the -ta and add -a, giving klikkaa-. Normally, the 3rd person singular lengthens the final vowel, but since klikkaa- already ends in a double vowel, Finnish spelling rules prevent a triple vowel. It remains klikkaa.

Why is the object linkkiä in the partitive case here?

The verb klikata (to click) typically takes a partitive object. In Finnish, interacting with digital elements like clicking links, pressing buttons, or scrolling pages is often treated as an irresultative action—you are interacting with the object, but not consuming or fundamentally altering it.