High Valyrian is a language with noun cases; these mark the role of the noun in the sentence. (This is similar to how German works too.)

The first two to meet are the nominative case and the accusative case. For now, it's enough to think of these as:

The nominative noun is the one which does a verb. (It is the subject.)

The accusative noun is the one which has the verb done to it. (It is the direct object.)

So:

• azantyssy is (the) knights when it is doing the verb.
• azantī is (the) knights when the verb is done to it.

Here The mother (the subject) loves (the verb) (the) knights (the direct object) , so it is the accusative azantī.

See also:

http://wiki.dothraki.org/High_Valyrian_Tutorial

http://wiki.dothraki.org/High_Valyrian_Noun_Cases

http://wiki.dothraki.org/High_Valyrian_Noun_Declensions#Solar-type:_loktys