Breakdown of Ég þekki þann í jakkafötunum.
ég
I
í
in / into / to (before the hour, in telling time) / per (in frequency expressions)
þekkja
to know
sá
that (sá, sú, það; þann)
Questions & Answers about Ég þekki þann í jakkafötunum.
Why is it þann instead of sá?
Þann is the masculine accusative singular form of the demonstrative pronoun sá (that / the one). It is in the accusative case because it is the direct object of the verb þekkja (to know), which always requires the accusative. The masculine form is used here because the speaker is referring to a man (maður) or a guy (strákur).
Could I use the verb vita here instead of þekkja?
No. In Icelandic, vita is used for knowing facts or pieces of information (like knowing a secret or knowing what time it is). When you are talking about knowing a person, recognizing someone, or being familiar with a place, you must use þekkja.
Why does the word for suit, jakkafötunum, end in -unum?
The base word for suit is jakkaföt, which is actually a neuter plural word in Icelandic (literally "jacket-clothes"). The preposition í requires the dative case here. The ending -unum is the standard suffix for any noun that is dative, plural, and definite (meaning it has "the" attached).
Is using í the normal way to say someone is wearing something?