YOU SAID:

if a dog does such a thing i'll be amazed

INTO JAPANESE

犬がそのようなことをしたら、私は驚くだろう

BACK INTO ENGLISH

I would be surprised if a dog did such a thing

INTO JAPANESE

犬がそんなことをしたらびっくりする

BACK INTO ENGLISH

I'd be surprised if a dog did that.

INTO JAPANESE

犬がそんなことをしたら驚くよ。

BACK INTO ENGLISH

I'd be surprised if a dog did that.