Puzzle Of The Day: 88
Three Letter Word
Here is a list of words:
INN PEN PET PIE TEE TIE
 A wise man tells three knights, “I have told each of you a letter found in the three-letter word. I have told none of you the same letter.”
 He then tells them, “None of you can tell how many vowels the word has.”
 Then they are told, “At this point still none of you can tell how many vowels the word has.”
 Now knight no 3 says he knows what the word is.
What is the word?