"The dog, it's tail wagging furiously, ran towards me."
Explanation:
* The sentence begins with a noun phrase ("The dog") as the subject.
* The expected continuation would be a verb phrase describing the dog's action.
* However, the sentence abruptly shifts to a participial phrase ("it's tail wagging furiously") that modifies the subject but does not directly describe the dog's action.
* The sentence then continues with a different verb phrase ("ran towards me").
This abrupt shift in grammatical structure creates a sense of informality, spontaneity, or even confusion. The speaker seems to have changed their mind mid-sentence, leaving the original grammatical construction incomplete.