"I chose to study Swedish."
Translation:Jag valde att studera svenska.
I noticed you asked the same question for the reverse case in another thread, so I hope you won't mind if I answer them both in one place.
The att typically functions as the word "to" does in English here. In other words, it is an infinitive marker, used to introduce another verb phrase:
- I chose TO study Swedish
- Jag valde ATT studera svenska
However, there's no point in using it for nouns, just like in English:
- I left TO my wallet at home <-- makes no sense
- I left my wallet at home <-- ah, much better
- Jag glömde ATT min plånbok hemma <-- doesn't work, for the same reason
- Jag glömde min plånbok hemma <-- bingo
That's the easy bit. Now, the tricky part is that there are essentially three groups of verbs in Swedish, in regards to using att before a verb phrase.
Modals never take the att. Swedish has a lot of modals and verbs that behave like them, and you'll eventually learn which they all are through trial and error. But for all other verbs, the att can either be mandatory or optional, and there is no way to tell which is which in advance, so I'm afraid you'll have to learn them all by heart.
I hope this helps at least a little!
Modality is the linguistic term for things that affect how factual information is communicated and interpreted. Modal verbs are verbs that have modality.
The most common ones are must, want, may, can, etc. These express obligation, desire, likeliness, ability, and so on. So in a sentence like "We might eat pizza", you use "might" to communicate the likeliness about the main verb "eat".
Many languages do this by conjugating the verb, but Germanic languages such as English and Swedish typically use a separate kind of verbs instead - the modals.