Exclamatory sentences of "It's a sweet dog."

[lagoo]

It's a sweet dog.


I changed it into three exclamatory sentences.
1)How sweet a dog!
2)How sweet a dog it is!
3)How sweet a dog is!




Could you tell me which ones are correct?

 

[Rover_KE]

THey are all unnatural.

'What a sweet dog it is!'

 

[emsr2d2]

You might hear the younger generation squeal something like "Oh! Em! Gee! How sweet is that dog!"

Note that while "How sweet is that dog" might look like a question, in this context, it's not. It's an exclamation requiring no response.