Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo.
James while John had had had had had had had had had had had a better effect on the teacher.The first sentence relies on three different senses of the word buffalo: the city Buffalo, NY; the noun (the large mammal that once roamed the prairie freely); and the transitive verb, which according to my Mac dictionary means to "overawe or intimidate (someone)." The Wikipedia article on this sentence provides the background and some syntactic trees for the sentence, but I'll give you a shortened rundown here:
Let's start at the beginning: Buffalo buffalo work together to mean the NP "buffalo that are in Buffalo". This NP occurs three times in the sentence:
[Buffalo buffalo] [Buffalo buffalo] buffalo buffalo [Buffalo buffalo].The remaining instances of buffalo in the sentence are the verb form. The first instance of buffalo as a verb is working with the NP [Buffalo buffalo] to modify the first NP [Buffalo buffalo]. You might reword the entire first part of the sentence (this will take care of the first five instances of buffalo):
The buffalo that live in Buffalo that buffalo (other) buffalo in Buffalo...Now the sentence is finished off with the transitive verb and its object, which also happen to be the buffalo in Buffalo:
The buffalo that live in Buffalo that buffalo (other) buffalo in Buffalo buffalo the buffalo that live in Buffalo.Is it a sentence? Sure. By loose-ish standards. Is it a good English sentence? No. Why would Buffalo buffalo be buffaloing other buffalo that live in Buffalo two times over? That just doesn't make sense. So while it is syntactically possible, it's semantically void of really meaning anything. While it may not be a sentence you'd want to use in an everyday conversation, it is a sentence you can wow your friends with at parties. Just think of all the debates you can get into once you proclaim, Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo is too a sentence in English!
The second sentence from above only works with added punctuation. In fact, its Wikipedia article states that this sentence shows why punctuation can be necessary in some sentences to understand meaning. The sentence with its appropriate punctuation looks like this:
James, while John had had "had", had had "had had"; "had had" had had a better effect on the teacher.Obviously, there was some sort of test, in which James wrote "had had" on the paper but John wrote "had", and the teacher preferred "had had" as the correct answer. All this took place in the past in a situation that required the past perfect to show that the activity was finished, thus leaving us with the seemingly (yet not) redundant pairing had had. In everyday speech, we often put the first had into a contraction, which sounds way less odd: I'd had three bananas before I realized that two would've been enough. That sentence just as easily could have started out with I had had three bananas... and been grammatically sound. That's what happens when a verb that has been grammaticalized as an auxiliary remains a main verb--have as an auxiliary (or helping verb) no longer has anything to do with its use as a main verb that usually (and loosely) shows some sort of possession (though "possession" doesn't even come close to fully describing the use of have as a main verb).
Again, is it a sentence in English? Yes. Is it one you're likely to come across? Not unless you're a teacher that left a blank on a test that should have been filled in with had had instead of had.
Do you know of any other crazy examples of sentences like these that people use to show off the oddities of language and syntax?