(if you're wondering about the pun in the title, that's a Stack Exchange meme for tag-related Meta questions)
The sentence tag currently has 17 questions and no tag excerpt or wiki. IMHO it's a very broad and ambiguous tag; I guess more than half of the questions here involve sentences in some way or another. If the sentence aspect is really important to the question, a more specific tag can be used, e.g. sentence-construction, sentence-meaning and sentence-structure.
I propose to get rid of it, and since something similar happened to the [sentences] tag it's probably a good idea to blacklist it (it seems that didn't happen back then, possibly because it involves a request to the Community Managers, ♦ moderators can blacklist tags themselves).