"This one is a boat."

Translation: Kesy lōgor issa.

[Koen486171]

why is this not "kesir", the aquatic substantive form of kesa? see https://wiki.dothraki.org/High_Valyrian_Pronouns

[Joel__W]

There are two forms of the substantive – one is for concrete things, one is for abstract things. Since it is a noun on its own, it doesn't have to agree with another noun in case and gender.

http://wiki.dothraki.org/High_Valyrian_Adjectives#Substantives