Vowels for idiots

The family was playing Boggle.  Not very successfully -- it was hard for young children to find +words, so Daddy gave tips to the children on how to find words more effectively:

Daddy: Look around the vowels. Do you know what vowels are?

Dominic: A-E-I-O-U

Pia: Daddy, if you have no brain you will think that vowels are A-N-G-T-X

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