Here's why:
* Short vowel sounds are typically represented by the letter itself (a, e, i, o, u) and have a short, quick sound.
* The "e" in "break" is followed by a consonant ("k") and another consonant ("another letter") which creates a closed syllable. This usually indicates a short vowel sound.
Think of the word "bread" or "bed" - both have short vowel sounds.