Here's why:
* Short vowel sounds are typically quick and sharp. Think of the sound you make when you say "cat," "dog," or "pen."
* Long vowel sounds are typically drawn out and are often represented by the vowel letter followed by a silent 'e' at the end of the word.
Since the "a" in "rake" has a short sound, similar to the "a" in "cat", it's considered a short vowel sound.