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Miau - a cat lover or most probably meaning that the motor purrs....
Blue envy? - I thought the colour associated with envy was green! I suppose because his/her car was blue, it was changed to blue.
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Good Nanna - Nanna is a term used for Grandmother.
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Misschief - Here it think it could be interpreted as mischief = naughtiness or playful misbehaviour or maybe the young lady is a boss - miss chief.
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Nitrogen - they must have just taken the cue from the car's name - Nitro.
Enigmatic - I find it funny when people use numbers instead of letters in a word.
Mrs Angry - hope she's not always angry, could be scary to drive behind or maybe ahead of her, no?
Hope you enjoyed the blue number plates, which one was your favourite?
I might show some black number plates next time.
Related posts :
http://sami-colourfulworld.blogspot.com.au/2016/04/personalised-number-plates-i.html