*** Guide-to-Links ***
B
B is used in a number of situations, involving relative clauses
and questions. It is most often used with transitive verbs.
Transitive verbs have an O+ connector, which can be satisfied
by a noun to the right. However, there are also various ways
in which a word to the left may satisfy this need, such as
relative clauses and questions; thus transitive verbs have a
"B-" disjoined with their "O+". B links are also used to
connect the main noun of a subject-type relative clause to the
verb. And they are used for so-called prepositional
prepositioning, in which the object-need of a preposition is
satisfied by a preceding word: "The MAN we talked TO is here".

B links interact very heavily with post-processing. It
will be noted that there are many kinds of subscripted B+
connectors; many of these subscript distinctions are used only
for post-processing, not for controlling actual linkages.

     Contents
     1. B- on verbs
     2. Relative clauses
     3. Object-type questions
     4. Indirect questions
     5. B links involving dependent clauses
     6. More about dependent clauses in indirect questions
     7. Transitive adjectives
     8. "Whatever", "whoever"
     9. Comparatives
     10. Prepositional prepositioning
     11. Noun-modifying preposition-object relative clauses

B- on Verbs
Transitive verbs have B- connectors disjoined with their
O+ (and any other complement connectors they may have such
as TO+ or TH+). Every finite verb also has a B- disjoined with
its S+, for use in subject-type relative clauses. This B- is
conjoined with RS+. Ordinary transitive verbs thus have the 
following:

	destroyed: (S- or (RS- & B-)) & (O+ or B-);

Relative Clauses
B is used in restrictive relative clauses (i.e. those without
commas), to connect the main noun to a verb in the relative
clause (whether the relative clause is subject-type or 
object-type). In object-type clauses it connects to the main
verb; in subject-type clauses it conects to the finite verb.

             +-------B-----+
             +-R-+-S-+--PP-+
             |   |   |     |
	The dog  I  had chased was black

	     +---B---+
	     +-R-+-RS+-PP-+
             |   |   |    |
	The dog who had chased me was black

Bs and Bp are used to enforce noun-verb agreement in subject-type
relative clauses; these are exactly analagous to "Ss" and "Sp".
So, "The dog who chases me is black", "The dogs who chase me 
are black" are accepted; "*The dog who chase me is black" is 
rejected.

See "R" for a fuller explanation of relative clauses.

Object-type Questions
Bsw and Bpw are used for object-type questions, in which the
object is a simple question word like "which", "what", "who",
or "whom". Such words therefore have "B*w+" connectors.

	 +-----Bsw---+
         |   +---I---+
         |   +SI-+   |
         |   |   |   |
	Who did you see yesterday

Bsm and Bpm are used for object-type questions, in which
the object-phrase contains a noun:

	        +----Bsm---+
                |  +---I---+
          +D**w-+  +-SI+   |
	  |     |  |   |   |
	Which dog did you buy

This construction uses the same B- connectors on verbs that
object-type relative clauses use. However, the B#m+ connector
on nouns used is not the one used in relative clauses. Note
that in the above construction, the Bsm satisfies the main
requirement of "dog"; "dog" need not (in fact may not) also
serve as a subject or object of a clause (*Which dog ran in
the park did you buy?). Thus, whereas the "R+ & B#+" complex
on nouns is optionally conjoined with the main "S+ or O-..."
complex, the B#m+ is disjoined with the main complex.

	dog: (R+ & Bs+) ...& ((S+ & {Wd- or...}) or O- or Bsm+...)

B#m+ connectors may only be used with question-word determiners
("what", "which", "whose", "how[many/much]"): "*The dog did you
buy", "*The dog you bought". This is enforced by the fact that
the wall has to connect to the sentence somehow. Normally,
this is done through the subject of the sentence; nouns have a
"Wd-" conjoined with their "S+". Notice, however, that the
"Bsm+" on nouns is disjoined from the Wd-. When the Bsm+ is
being used, the sentence cannot connect to the wall unless it 
does so through the determiner - and the only determiners that
have W- connectors are question-word determiners. (Question-word 
determiners also have QI- connectors, used in indirect
questions: see below.) (Object-type questions also require 
subject-verb inversion: see "SI: Questions requiring subject-
verb inversion".)

"What" and "which" can act either as question-word determiners
or as complete noun-phrases; and as complete noun-phrases they
may occur in either subject- or object-type questions. Thus
they carry "(B*w+ or S**w+ or D**w+) & (QI- or W-)". 

Indirect questions
The above discussion of B links in questions applies to
indirect questions as well.

                  +---B(s)--+
        +-S--+-QI-+    +S(s)+
        |    |    |    |    |
	I wonder who Dave  hit

Noun-phrase question-words have "(W- or QI-) & B*w+": the W- 
is used in questions, the QI- in indirect questions. See "QI".

B links involving dependent clauses
Suppose the verb making the B connection is in a dependent
clause:

         +------------B--------------+
         |   +---I---+               |     
         |   +SI+    +-C--+-S--+--I--+
         |   |  |    |    |    |     |
        Who do you think Bill will bring

This construction is handled perfectly well under the current
arrangement. Similarly with relative clauses and indirect
questions: "I wonder who you think Bill will bring", "The
man who I think you met yesterday is here".

There is a problem, however: there are constraints on the
way that a B link can be made out of a dependent clause.
Specifically, a B link cannot be made to a word that is
within a subordinate clause (1), an indirect question (2),
or a relative clause (3).

         +----------------B(s)------------+
         |                   +--Cs-+--S(s)+
         |                   |     |      |
    1.* Who did you leave because Bill mentioned?

         +-----------B(s)------------+
         |                 +--Cs+S(s)+
         |                 |    |    |
    2.* Who do you wonder why Bill  hit?


         +--------------B(r)-----------+
         |                 +-----B(r)--+
         |                 +--R--+RS(r)+
         |                 |     |     |
    3.* Who do you know someone who likes?

This hold true whether the outer construction is a direct
question, an indirect question (ex. 4-6 below) or a relative
clause (ex. 7-9).

	4.*I wonder who you left because Bill mentioned
	5.*I wonder who you wonder why Bill hit
	6.*I wonder who you know someone who likes

	7.*The man who you left because Bill mentioned is here
	8.*The man who you wonder why Bill hit is here
	9.*The man who you know someone who likes is here

Linkages are found for all of these sentences, under the
current arrangement. They are weeded out in post-processing.
In each case, a domain is started at the beginning of the
dependent clause. Notice that the domain started will then
spread back through the B link. However, the subordinate
domains started in these cases are of different kinds. Verbs
that take clausal complements (like "said") have Ce+
connectors, which start 'e' domains; question words and
conjunctions, however, have Cs+ connectors, which start 's'
domains, and relative pronouns have R+ connectors, starting
'r' domains. We then dictate that 's' and 'r' domains simply
are not allowed to stretch back before the root word (the left
end of the starting link). (We call such domains "bounded
domains".) Thus the incorrect sentences above are prohibited.
In sentence 1 above, for example, the Cs on "because" starts
an 's' domain; this spreads through the B link to "who", which
is to the left of "because"; this violates the "bounded
domain" rule.

As described above, finite verbs also have "B-" connectors
for use in subject-type relative clauses. These cannot be
used, however, unless the finite verb can also make a RS
connection to the left. The only way this can happen in
questions is if the question contains a subordinate clause:
"Who do you think will come?" (See "RS".) 

More about Dependent Clauses in Indirect Questions
Dependent clauses within indirect questions are, again,
handled quite naturally:

                  +------Bsw(s(e))----------+
        +-S--+-QI-+    +S(s)+-Ce(s)-+S(s(e))+
        |    |    |    |    |       |       |
	I wonder who Dave  thinks Bill     hit

Note that in this case, it is very important that the
B#w link be a "restricted link": the 'e' domain begun
by the Ce must not be traced through it, otherwise it
would spread to the rest of the sentence.

Another false positive arises here at the linkage level:
             
             +-----------O(s)----------+
             |            +-QI-+D**w(s)+
             |            |    |       |
	*I read I don't know which   book

Again, this is handled by post-processing. Since 's' domains
are "bounded", they may not reach back before the root word. 
Thus the above construction is prohibited in post-processing.

Transitive adjectives
 Certain adjectives, when used predicatively, can take
transitive infinitives as complements: "It is easy to use".
Such adjectives take B+ conjoined with TOt+; see "TO: Other
Kinds of TO Connectors". 

"Whatever", "whoever"
Bsd is used for words like "whatever" and "whoever". These
words may take object-type relative clauses: however, they
simultaneously serve as the subject or object of a main clause.
Therefore, they take "(Bsd+ or Ss*d+) & (Os- or Ss+)".

           +---------Ss---------+
	   +------Bsd--------+  |
	   |		     |  |
	Whatever you want to do is fine

Since the "whatever" phrase seems to constitute its own clause 
here, a domain must be started for such constructions. Therefore 
we make "Bsd" domain-starting. A domain must also be started for 
the corresponding subject construction:

           +--------Ss-------+
	   +--Ss*d--+        |
	   |        |        |
	Whatever pleases you is fine

Therefore we make "Ss*d" domain-starting as well.
	
Comparatives        
In comparatives, the second half of the comparative can
take a transitive verb with no object: "I have more books
than she has", "She has as many friends as I have". A B+ is
needed here to satisfy the "B- or O+" requirement on
transitive verbs. Thus "than" and "as" have a "Bc+" connector.
Post-processing ensures that this is only used in certain
kinds of comparatives: "*I am smarter than she has". See 
"MV: Comparatives V".

Prepositional Prepositioning
99% of the uses of B links involve hooking to a verb on the
right: either satisfying the object-need of a transitive verb
(most often) or the subject-need in "RS" constructions (see
"RS"). B- connectors appear analogously on prepositions,
however, when the object-need of a preposition can be
satisfied by a word on the right. For this construction to be
valid, the preposition involved must be modifying a verb, not
a noun (i.e., it must be using an MVp- connector, not an Mp-):
	
	1.Who did you talk to
	2.Which room did you sleep in
	3.*What country did you meet a man from
	4.*How many legs did you see an insect with
	5.Who did you take a picture of (!)

Sentences 3 and 4 are perhaps grammatical, but not if we take
the preposition to modify the noun. For this reason, we do not
directly disjoin B- with J+, as we disjoin B- and O+; rather, 
prepositions carry

	(J+ & (Mp- or MVp- or ...)) or (MVp- & B-)

(The exception is "of", as shown by ex. 5; here, B- must be
conjoined with Mp-.) Beyond this, B- on prepositions can be
used in all the ways it is used on verbs: in relative clauses
("The man who I talked to is here"), with transitive
adjectives ("He is easy to talk to"), with "whatever"
("Whatever you like to work with is fine"), and so on.

Noun-Modifying Prepositional-Object Relative Clauses
A final use of B occurs in relative clauses where the focus of
the clause is the object of a noun-modifying preposition.

                      +----Bpj-----+
               +--MX--+-M--+-Jr+RS-+
               |      |    |   |   |
	The doctors, many of whom are surgeons, were angry

                         +--------Bpj-----+
              +-----MX---+-M-+-Jr-+Cr-+-S-+
              |          |   |    |   |   |
	The book, the author of which I know personally, is good

We already have a mechanism for allowing noun phrases
surrounded by commas to modify other noun phrases: this is the
MX link (e.g., "The doctor, a good friend of mine, is
here"). We use that same mechanism here. In this case,
however, the modifying noun acts like the antecedent of a
relative clause. It may either act as a subject, in which case
it must be followed by an ordinary finite verb phrase; or it
may act as an object, in which case it must be followed by a
phrase containing a transitive verb but no object. The "B/RS"
system is already in place to handle this. In relative
clauses, the relative pronoun provides the needed "RS+" to
allow for the following finite verb; in object clauses, it
makes a "Cr" link to the subject of the relative clause. In
this case, "which" and "whom" can serve the same function. The
only difference between this usage and an ordinary relative
pronoun is that here the relative pronoun is also acting as a
prepositional object. Thus we give it "Jr".

	which: (R- or Jr-) & (RS+ or Cr+);

We must then allow the main noun of a comma-modifier phrase to
act as a relative antecedent. Thus we give nouns an optional 
"B#j+", conjoined with their MX-:

	dog: ...(S+ or O- or J- or ({Bsj+} & Xc+ & Xd- & MXs-))

There are several false positives to be avoided here. First, we
must prevent the Bsj being used without the appropriate relative
pronoun. Subject constructions ("The doctors, many of them are
surgeons"), will be prevented anyway, because there is no "RS"
to connect to the verb. But object constructions must be prevented:

	      +---MX----+---Bsj-+
              |         |       |         
       *The book, the author I know personally, is excellent

(Actually this construction will be accepted anyway; the comma phrase
will be treated as an ordinary noun-phrase, a noun followed by
a relative clause, as indeed it is.) Secondly, we must prevent
the "which" from being used in the wrong place:

                     +-Mp-+-Jr+----Cr--+
                     |    |   |        |
       *I saw the author of which the book was excellent

(This sentence too will be accepted anyway, using an Mj construction,
but in any case the Jr parse is redundant and should be avoided.)
We solve these problems in post-processing: we require that the
Jr must occur in the same group as B#j. (This goes both ways:
a Jr requires a B#j, and a B#j requires a Jr.)

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