Hello :-)

It's possible to make a grammatically correct
(but nonsensical) Old Norse sentence that consists
of the letter á repeated five times.

"Á á á á á."

This could mean:

A river has a grandfather on a sheep.

ái (ancestor)
á[a]
á[a]
á[a]

ær (sheep)
á
á
ær

á (river)
á
á
ár

Case order nom-acc-dat-gen as usually.

According to a joke in Fagrskinna people also
did a lot of yelling "Á!" in battle.

Kveðja,
Haukur