Breakdown of Olin niin hämmentynyt, että unohdin kaiken.
olla
to be
unohtaa
to forget
niin
so
että
that (conjunction)
Questions & Answers about Olin niin hämmentynyt, että unohdin kaiken.
How does the niin ... että structure work in this sentence?
It translates directly to the English "so ... that" structure. The word niin (so) emphasizes the adjective hämmentynyt (confused), and the consequence is introduced by että (that).
Is hämmentynyt a verb or an adjective here?
It acts as an adjective, but it is actually the past participle (often called the NUT-participle) of the verb hämmentyä (to get confused). It literally describes someone who has gotten confused.
Why is the object kaiken instead of the basic form kaikki?
The verb unohdin (I forgot) needs an object. Because you forgot the entirety of it (everything), it acts as a total object. For a regular action like this, the total object takes the accusative ending -n, changing kaikki to kaiken.
Why is there a comma before että?
In Finnish grammar, you must always place a comma before the conjunction että when it introduces a new clause. This is a strict rule in Finnish, unlike in English where "so ... that" sentences do not use a comma.