All sentences are related.

Okay, clearly that needs a bit more explanation. The bottle of beer has no beer in it seems totally unrelated to My mother told me never to eat glass. Nonetheless, they are related. Much as you're related to your fifth cousin, nineteen times removed. Simply, each contains a subject, each contains a verb, and each contains an object. Or, to put it into brand new terms (to those of you who may not eat, drink, breathe linguistics), a sentence has a noun phrase, an auxiliary, and a verb phrase. S => NP Aux VP. Remember this equation. It will be on the final exam. Here follows an example of the simple sentence I am a boy, which is composed as S => NP (Noun) Aux VP (Verb NP (Det. Noun)):

      S
    / | \
  NP Aux VP
 /    |    \--\
N (present) V  NP
|           |   |--\
I          am  Det. N
                |   |
                a  boy.

How to diagram like the stars:

As has become rather evident in this writeup, I am not diagramming sentences in the traditional way. You'll see nothing like "direct object" or "main verb" with slashes and lines coming off at every direction in these diagrams. The point of these diagrams is not to explain how each word acts in a sentence, but to explain how the sentence itself works.

As stated, the traditional sentence is laid out in a simple S => NP Aux VP. That much makes sense. But what, really, is a NP? What's a VP? When does an Aux actually make sense? It's important to break down just what these things are, first, before we can do anything else.

We'll begin with the noun phrase. The noun phrase is the hardest working phrase out there. It's the subject, it's the direct object, it's nestled with prepositional phrases, with adjectives, and with other verbs. At its core, however, is that gem of grammar, the noun. Each noun phrase must include a noun, if nothing else. You can throw in almost anything else, but the noun must exist. So, boy is a perfectly good NP: NP => Noun ("boy"). Toss in a few extra words, the happy boy, and you're still treading in good NP areas: NP => Det ("the") AP (Adj ("happy")) Noun ("boy"). Fooled you there, didn't I? An AP is an adjectival phrase, which is misleading because it can also be an adverbial phrase. Fortunately, both those words start with the same letter, so the abbreviation can work either way. An AP requires an adjective or an adverb. We call it a phrase, but, really, it's just one or the other. Or several. But there's nothing else that can go in there. The happy, purple, startled boy breaks down into NP => Det ("the") AP (Adj ("happy") Adj ("purple") Adj ("startled")) Noun ("boy"). That's just fine.

Next comes the auxiliary. Auxiliaries aren't really that active in our world of English sentences. As known, English verbs are relatively unique in the world's languages because ours only come in past or present tense. We have no future tense verb. In order to make a future tense, we must come up with an auxiliary, most commonly "will" or "shall" or some such nonsense. When diagramming simple-present or -past tense sentences, our auxiliary is merely noted as (present) or (past), taking up the space where an auxiliary would go, but just paying lip service to the fact that no such word actually exists. Breaking down the short sentence I will kill you fills our auxiliary position nicely: S => NP (Noun ("I")) Aux ("will") VP (Verb ("kill") NP (Noun ("you"))). However, the slightly awkward present-tense form gets a placeholder: S => NP (Noun ("I")) Aux (present) VP (Verb ("kill") NP (Noun ("you"))).

Finally we've come to the verb phrase, the real workhorse of the sentence, and not just because all the action goes on there. The VP, at its minimum, must contain a verb. Nothing more, really, is required. kill is a perfectly find VP, though a bit empty: VP => Verb ("kill"). You can happy throw in prepositional phrases, noun phrases, and adjectival phrases quite happily. Kill you slowly on the playground breaks apart into: VP => Verb ("kill") NP (Noun ("you")) AP (Adv ("slowly")) PP (Prep ("on") NP (Det. ("the") Noun ("playground"))).

I lied in that last paragraph. Finally, actually, is a complimentary phrase, or CP. I left these to the end because they change everything around. When using a CP, you don't need a NP, per se. Suddenly, S => CP Aux VP is perfectly fine. Confused? Let's talk slightly more complex sentences. I like that, but I love this. adds a new level of phrase diagramming, because the ", where" breaks out another phrase, yes? It looks like this: S => NP (Noun ("I")) Aux (present) VP (Verb ("like")) NP (noun ("that")) CP (Comp ("but") NP (noun "I") Aux (present) VP (verb ("love")) NP (noun ("that"))). Did you see what happened there? When the CP was introduced, it was as though a new S was tacked on. A CP requires the same things. S => NP Aux VP => CP. Make sense? Let's move on.

Making waves.

This idea of sentence relatedness was first put forth by the linguistic patron Noam Chomsky in the 1950s and 1960s and revolutionized the field of linguistics and cognitive psychology. He used it was a tool in describing his idea of Universal Grammar, which challenged the idea that language is taught, rather than acquired. In any event, he broke down sentences into their ability to be transformed into two basic groups: Deep structure and surface structure. That is, the meaning of the sentence vs. the words used in a sentence.

Different structures do not always change the meaning of a sentence. That is the nature of sentence relatedness. Take the following examples:

  1. The bottle shattered loudly. * The bottle loudly shattered.
  2. I stare at my neighbors through a telescope. * Through a telescope I stare at my neighbors.
  3. Jim Henson killed Kermit. * Kermit was killed by Jim Henson.
  4. You know that I know that you know. * You know I know you know.
  5. My liver is dying. * Is my liver dying?

You'll note, of course, that 1-4 change the structure of the S => NP Aux VP in the second sentences and the meaning remains unchanged. In 5, however, the structure was changed to S => Aux NP VP, which is conveniently how we create simple questions. In the five sentence pairs, the five main transformational rules are illustrated. The first 4 show simple transformations of surface structure (the meaning remains the same). The last sentence shows a deep structure change (the meaning of the sentence is changed). Let's begin with some explanation on those rules.

Transformational rules:

Recall sentence pair #1. If you cannot, cast your eyes up a few inches to remind yourself the difference between the two sentences. As far as meaning is concerned, the two sentences mean exactly the same thing: A bottle shattered, and it was loud. In neither sentence do we know what kind of bottle it was, whether it contained liquor, or if it was shattered on top of anyone's head in a drunken barroom fight. The same information is given in each. Quite simple. What changes, however, is the VP part of our equation. When we humans begin assimilating the language into our brains, we learn that modifying the VP in this way is perfectly okay. In this case, it is a surface structure that is changed. The VP is changed from Verb + Adverb (VP => V AP (Adv)) to Adverb + Verb (VP => AP (Adv) V). The sentence structure transformations:

                      First Sentence
           S
         / | \
       NP Aux VP
   /--/    |    \-----\
Det. N  (past)   V     AP
 |   |           |      |
The bottle  shattered  Adv
                        |
                     loudly.

---------------------------------------------------------

                      Second Sentence

           S
         / | \
       NP Aux VP
   /--/    |    \------\
Det. N  (past)   AP     V
 |   |            |     |
The bottle       Adv shattered
                  |
               loudly

The second pair of sentences moves the prepositional phrase through a telescope from the VP to the main NP. That's perfectly legal. First, let's talk about prepositional phrases (PP), and the new letters you'll assign to how they are created. A PP requires a preposition (P), and a NP. In the first sentence, the VP is broken up into a verb, "stare" and then the two prepositional phrases, "at my neighbors" and "through a telescope." The structure then is S => NP Aux. VP (V PP (P Det. NP (Noun)) PP (P Det. NP (Noun))). The Aux. in this case is merely a placeholder admitting that the verb is in present tense, so an auxiliary is not needed. The second sentence was transformed to S => NP (PP (P NP (Det. Noun)) Aux. VP (V PP (P NP (Det. Noun)). Maybe a diagram is in order.

                      First Sentence

      S
    / | \
  NP Aux VP
 /    |    \----\------------------\
N (present) V    PP                 PP
|           |     |-\                |---\
I         stare   P  NP              P    NP
                  |  |----\          |     |----\
                 at Det.   N      through Det.   N
                     |     |               |     |
                     my neighbors          a telescope.

---------------------------------------------------------

                      Second Sentence

                            S
                          / | \
                        NP Aux VP
          /------------/    |    \---\
        PP            N (present) V   PP
    /----|            |           |    |-\
   P    NP            I         stare  P  NP
   |     |----\                        |   |----\
Through Det.   N                      at  Det.   N
         |     |                            |    |
         a telescope,                      my neighbors.

Our next exciting pair of sentences shows you what every English teacher abhors: the passive sentence. The first is quite active, showing Jim Henson brutally murdering a little green puppet, in an act of passion. The second shows that sad, sad puppet merely expiring at Henson's hands, perhaps of old age. No teacher likes a passive sentence, and no one wants to see a sentence diagram showing how it is done. All that needs be noted, however, is that the subject of the sentence was moved in the second form without changing the meaning of the sentence.

The fourth and final of the change-the-sentence, don't-change-the-meaning transformations is simply called moving that. What happens when this transformation comes into play? Well, the phrase tells all: you move that. Sometimes this means moving that out of the sentence at all, sometimes you move one in. Meaning-wise, "that" changes nothing.

Finally we've come to the easiest way to make a question in the English language: moving the auxiliary from the middle of the diagram to the front of the diagram. Let's take a look:

                      First Sentence

         S
       / | \

     NP Aux VP
  /---|  |   |
Det.  N  is  V
 |    |      |
My  liver  dying.

---------------------------------------------------------


                      Second Sentence

         S
   /---/  \
Aux   NP    VP
 |    |---\   \
Is   Det.  N   V
      |    |    \
      my liver  dying?

Tying it together.

So, you ask yourself, why is this so damn important that you had to read through all this? Well, the point of this is to explain how sentences in English are related. There are rules to which we adhere, whether we intend to or not. You can use standard diagramming until you're blue in the face, and you may be no closer to how sentences come together. By breaking these sentences into basic phrases, it becomes much easier to find how they happily exist. By looking at them this way, it is quite obvious that moving the VP to the front of your NP and Aux is a ludicrous idea, not just because it breaks the S-O-V system, as well as the phrase system I've laid out here, but because it feels funny in your mouth. *Dying my is liver, though the verbs are conjugated properly, still makes no sense. *My liver dying is makes just as little sense, even though it follows a S-O-V layout.

One of the great joys of linguistic study is that we do not work inside of a vacuum. You remember arguing (in your mind) with your 5th grade English teacher about why many of English's rules are silly.

But we're left with a concept that will help tie a piece of string to each and every sentence you've ever uttered: they're all somehow the same. It's not your direct objects and secondary verbs. It's your noun phrases and verb phrases. Use your newfound knowledge of sentence structure to give your writing a new style. Listen as people speak to hear how they actually form their sentences--oftentimes it's different than what you might type. As such, you may pick up something that most authors simply can't find: reality.


All this various information was gathered in my brain over the past several years. I am eager to explain any of this subject matter in more detail (heavens save me if I didn't cover everything) should you wish it. Thanks for getting all the way to the bottom.

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