The correct answer to this open question is the following.
The aspect of language that is giving you trouble is "phonemes."
In Linguistics, a phoneme is the smallest unit of sound speech. We can say it is the letters that form a word, but in speech, we call them phonemes. For instance. The word "boy" has three phonemes: "b," "o," and "y."
The Nazi loss in the Battle of the Bulge sealed the Third Reich's fate-- the Allies were free to invade Germany, causing its downfall.
Huns, Vandals and Visigoth :)
