*** Guide-to-Links ***

W is used to attach the subject of main clauses to the wall (hereafter "the wall" means the left-wall). Almost all kinds of main clauses - declaratives, most questions (object-type, subject-type, where/when/why, and prepositional), and imperatives - use a W of some kind to attach to the wall. The only exception is "yes-no" questions, which attach to the wall with Q. See "Q". The WV attaches the main verb of the main caluse to the wall; thus, W and WV form a cycle. See WV for more details.

  |          |
/////   The dog ran (Wd)
/////       Who did you hit (Wq)
/////       Who is coming (Ws)
/////       To whom did you speak (Wj)
/////       Go away (Wi)
/////       Going shopping (Wg)
/////       ... like  wedding cakes (We)
/////       Under the tree slept Jim (Wp)
/////       Under the tree (Wl)
/////       Cheaper than dirt, slime is greener (Wr)
/////   The twin (Wa)
/////       That I did not know (Wt)
/////       What do you think? (Wb)
/////       Why run away? (Wv)
/////       Why not? (Ww)
/////       How many times? (Wh & Wa)

Note that the wall is automatically inserted at the beginning of every sentence, and is then treated like a normal word; by the connectivity rule, therefore, it must make some kind of connection to the sentence. The wall thus has "W+ or Q+".

W is also used to attach clauses back to coordinating conjunctions in declarative sentences; coordinating conjunctions thus have "CC- & (Wd+ or Wq+ or Ws+)". CC then makes a link back to the subject of the previous main clause.

Wd: Declarative Sentences

Wd is used in ordinary declarative sentences, to connect the main clause back to the wall (or to a previous coordinating conjunction). Nouns carry Wd-, optionally conjoined with their S+ connectors. Wd- on nouns is directly disjoined with C- (used in dependent clauses) and R- (used in some relative clauses); see "C".
      dog: (({@CO-} & Wd-) or ({@CO-} & C-) or R+) & S+

Wp, Wr: verb modifier inversions

Wp and Wr are used to avoid a link-crossing whenever a verb modifier occurs first in the sentence, before the subject. This is required because the usual use of Wd to the head-noun of the sentence would interfer with the link between the modifier and verb.
    |        +<---------PFt<---------+
    +-->Wp-->+                       |
    |        |                       |
  /////    here the remains can be found

    |        +<-----PF<-----+
    |        |              +--SIs---+
    +-->Wp-->+              |        |
    |        |              |        |
  /////    down the stairs came the dog   

The Wp link is used for both locative and directive inversions. For comparative inversion, Wr is used to link to the fronted comparative adjective. For quotative inversion, the CP link is used. For questions, Wq, Ws and Wj links are used; see below. For locative declarations without a verb, the Wl link is used.

Wq, Ws, Wj, Ww, Wb, Wv, Wh: Questions

Wq, Ws, Wj, Ww, Wh and Wb are used to connect many types of questions to the wall: subject questions (Ws), object questions (Wq and Wh), where/when/why questions (Wq and Ww), adjectival questions (Wq), prepositional questions (Wj), topic questions (Wb), and action questions (Wv). Each of these link types interacts heavily with post-processing. See "SI" for an explanation of Wq and Ws; see "JQ" for an explanation of Wj. See Wt below for an example of Wb. The Ww link is used for questioning exclamations in which there is no head verb that can link to the wall. When there is a head verb, then Wq is used.

The Wv link is used for "why?" questions with an action verb: "why run away?"

The Wh link is used for "how?" questions with an object:

      |      |    |     |
    /////   how many times.n
This is unusual, in that two W links appear: one to the question-word, and one to the object. This is analogous to verb questions, where WV links the wall to the verb; here, however, the Wa link is used to connect the object to the wall.

Wt: Topic sentences

Most sentences start with a subject; a few start with the topic, instead. The Wt link is used to link the topic to the wall. For example:
            |           +-----I*d-----+
    +---Wt--+--Rn-+-Sp*i+---N--+      |
    |       |     |     |      |      |
  /////   that    I    did    not   know
The B link points to the left, from the head-verb (know) to the topic (that). In the above, ther is no way to link the subject (I) to the wall, without crossing the B link. Thus, the Wt link serves to start the sentence.

Topic questions have a similar structure:

            |     +-----I*d----+
    +---Wb--+--Rw-+-SIp-+      |
    |       |     |     |      |
  /////   what   do    you   think

Wo: Infinitive sentences

Examples include: "To be continued", "To be determined later."

Wa: Affirmative replies

Wa is used to connect null-verb sentences to the wall. Null-verb sentences typically occur as affirmative answers to questions: "What did you see?" "A red car." "Who was in it?" "John's evil twin." "When did this happen?" "June 10th." Thus:
    |    +----Ds---+
    |    |   +--A--+
    |    |   |     |
  /////  a red.a car.n 

Wi: Imperatives

Wi is used to connect imperatives to the wall.
     |     |
  /////    Go away

Imperative verb forms have "Wi-", conjoined with their complement connectors. Since the imperative verb form is always the same as the infinitive form (and the plural, in every case except "be"), the same expression can be used. Infinitive verbs thus carry

      (Sp- or I- or Wi-) & [complement];

Wg: Participles

Wg is used to connect participles to the wall. These frequently occur as answers to interrogatives, such as "what are you doing?", "What did you do?", or are diary entries, to-do list entries.
     |                  |
  /////               Going shopping!
  /////               Sang with the church choir today
  /////    Frequently chats with the grocer

Wn: Nominal objects

Wn is used to connect nominal object sentences to the wall. These are sentences having only the object, and inverted: for example, "what a mess [this is]" or "what a great day [it is] today".
     +---Wn--+  +Ds**c+
     |       |  |     |
  /////    what a    mess

Wx: Opinion expressions

Wx is used to connect opinion expressions to the wall.
     +--Wx--+    |
     |      |    |
  /////   sad.a  !

Wl: Locative expressions

Wl is used for locative expressions that don't have a verb. These commonly occur as replies to questions such as "where is it?" or "when did happen?"
     +--Wl--+  +-Ds-+
     |      |  |    |
  /////    on the table
Such expressions can be conjoined, and become quite long; for example, "on the table, just to the left of the lamp, just over there".

Wc: Coordinating Conjunctions

There are a number of words that serve to link clauses together: coordinating conjunctions like "and" and "but", and subordinating conjunctions like "after" and "because".
      |        |   |
    John left but he returned later

           |    |   |
    John left after I saw you

Note that subordinating and coordinating conjunctions use very different linking structures. First of all, both the left-pointing and right-pointing connectors on the conjunctions are different; "but" has "CC- & Wd+", "after" has "MVs- & Cs+". Secondly, coordinating conjunctions connect back to the subject of the previous clause, subordinating conjunctions to the verb. There are several reasons for making these distinctions. First of all, coordinating conjunctions may not be used in relative clauses:

      *The man I tried to hit but Jane stopped me is here
      *The man I tried to stop Jane but she hit is here
      *The man I hit but Jane comforted is here

(There are other constraints on relative clauses: the main noun of a relative clause may not link to something inside an embedded clause. We handle this using Ce and Cs; see "C".) So, we need to prevent these constructions. Coordinating conjunctions have another related property. They may be used to connect clauses in sequence, like subordinating conjunctions. But whereas subordinating conjunctions seem to link in a nested way, with each modifying the last, coordinating conjunctions seem to "leap" over any preceding subordinating conjunctions:

          |            |   |   |      |     |     |
     1. John screamed when I arrived after Sue  left (seems right)

                           +---- ? ---+
          +------------+-C-+-S-+      +--W--+--S--+
          |            |   |   |      |     |     |
     2. John screamed when I arrived but   Sue   left (seems wrong)

          +------------+-C-+-S-+      +--C--+--S--+
          |            |   |   |      |     |     |
     3. John screamed when I arrived but   Sue   left (seems right)

We handle this in the following way. In the first place, coordinating conjunctions link to the left not with MVs-, like other conjunctions, but with CC-.

      and but: CC- & W+;
      dog: {R- or C- or (W- & {CC+})} & S+...;

Note that subject nouns may make a CC connection to the right, but only if a W is being made to the left (i.e., if the noun in a subject of a main clause), not if a C is being made. In other words, while subordinating conjunctions connect to the main verb of the nearest clause to the left, coordinating conjunctions connect to the subject of the nearest main clause to the left. Thus ex. 3 above is allowed, but ex. 2 is prevented. The problem with relative clauses is solved also. In relative clauses, the main subject of the relative always makes either a C- or an R- to the left, and neither one is conjoined with CC+; so no coordinating conjunctions can appear.

Note that the above expressions also allow coordinating conjunctions to link clauses in sequence:

          |            |    |       |   |
        Jane screamed and Fred ran but Dave cried

Coordinating conjunctions may also connect directly to the wall: "And Jane screamed". Thus they carry a "Wc-" connector, which can link to the wall's W+. Furthermore, a coordinating conjunction may link to a following question, rather than to a declarative clause. They may not, however, link from a question to a declarative clause:

   I know you don't like Joe, but why did you send him that nasty note
   *Why did you send Joe that nasty note, but I know you don't like him

Thus we give such conjunctions the following:

    (CC- or Wc-) & (Wd+ or Wq+ or Ws+ or Qd+);

Another reason for distinguishing between W and C is that certain openers like participle openers may be used in main clauses but not dependent ones; see "CO: Participles as openers".

We: Ellipses

We is used to connect ellipses to the wall.
     |       |
  /////     ... like a shot
An ellipsis denotes the intentional ommission of a part of a sentence. Very little can be assumed about what has been omitted, other than that it must have been grammatical. Thus, We- is conjoined with a reasonably broad set of generic links, so that the trailing phrase can parse properly.

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