The sentence is incorrect because it does not end with a period.
Although the sentence is spelled correctly, the lack of a period at the end of the sentence makes it incorrect. For this reason, we must always pay close attention to the punctuation of texts.
The question presented above is incomplete. The full question is "He wore a very weird mask to the Halloween party. Is this sentence correct or incorrect?"
More information about textual coherence at the link:
https://brainly.com/question/2773425