Learn Finnish: Uusiutuuko luonto täällä nopeasti? - Does nature regenerate quickly here?

The base word is the adjective uusi (new). From this we get the verb uusia (to renew something). Adding the automative suffix -tua creates uusiutua, meaning to renew itself or to regenerate without an outside force. Finally, the -ko suffix makes it a yes/no question.

Does the -tua ending always mean to do something to itself?

Often, yes. The -tua or -tyä suffix frequently creates a reflexive verb (doing an action to yourself) or an automative verb (an action happening on its own). It changes a verb where someone does something to an object into a verb where the subject simply changes state on its own, like nature regenerating here.

Why is the question particle -ko attached to the verb instead of another word?

In Finnish yes/no questions, the -ko or -kö particle is attached to the specific word being questioned. Because you are asking whether the action of regenerating actually happens, the verb gets the particle and must be moved to the very front of the sentence.

How is the word nopeasti formed?

It is an adverb formed from the adjective nopea (quick or fast). By adding the suffix -sti to the adjective, you turn it into the adverb nopeasti (quickly). This is the most common way to make adverbs in Finnish, similar to adding -ly in English.