new resource doc on Phrase etc

lib/resource-1.0/abstract/Adverb.gf

@@ -10,7 +10,6 @@ abstract Adverb = Cat ** {
     PositAdvAdj : A -> Adv ;                 -- quickly
     PrepNP      : Prep -> NP -> Adv ;        -- in the house
 
-
 -- Comparative adverbs have a noun phrase or a sentence as object of
 -- comparison.
 
@@ -24,7 +23,7 @@ abstract Adverb = Cat ** {
 -- Subordinate clauses can function as adverbs.
 
     SubjS : Subj -> S -> Adv ;               -- when he arrives
-    AdvSC : SC -> Adv ;                      ---- REMOVE THIS?
+    AdvSC : SC -> Adv ;                      -- that he arrives ---- REMOVE?
 
 -- Comparison adverbs also work as numeral adverbs.
 

lib/resource-1.0/abstract/Cat.gf

@@ -29,6 +29,7 @@ abstract Cat = {
     Cl ;    -- declarative clause, with all tenses e.g. "she looks at this"
     Slash ; -- clause missing NP (S/NP in GPSG)    e.g. "she looks at"
     Imp ;   -- imperative                          e.g. "look at this"
+    SC ;    -- embedded sentence or question       e.g. "that it rains"
 
 --2 Questions and interrogatives
 
@@ -52,7 +53,6 @@ abstract Cat = {
 
     VP ;    -- verb phrase                         e.g. "is very warm"
     Comp ;  -- complement of copula, such as AP    e.g. "very warm"
-    SC ;    -- embedded sentence or question       e.g. "that it rains"
 
 --2 Adjectival phrases
 

lib/resource-1.0/abstract/Phrase.gf

@@ -1,21 +1,43 @@
+--1 Phrases and utterances
+
 abstract Phrase = Cat, Tense ** {
 
+-- When a phrase is built from an utterance it can be prefixed
+-- with a phrasal conjunction (such as "but", "therefore")
+-- and suffixing with a vocative (typically a noun phrase).
+
   fun
-    PhrUtt  : PConj -> Utt -> Voc -> Phr ;
+    PhrUtt   : PConj -> Utt -> Voc -> Phr ; -- But go home my friend.
 
-    UttS    : S -> Utt ;
-    UttQS   : QS -> Utt ;
-    UttImpSg, UttImpPl  : Pol -> Imp -> Utt ;
+-- Utterances are formed from sentences, questions, and imperatives.
 
-    UttIP   : IP   -> Utt ;
-    UttIAdv : IAdv -> Utt ;
-    UttNP   : NP   -> Utt ;
-    UttAdv  : Adv  -> Utt ;
-    UttVP   : VP   -> Utt ;
+    UttS     : S -> Utt ;                   -- John walks
+    UttQS    : QS -> Utt ;                  -- is it good
+    UttImpSg : Pol -> Imp -> Utt;           -- (don't) help yourself
+    UttImpPl : Pol -> Imp -> Utt;           -- (don't) help yourselves
 
-    NoPConj : PConj ;
-    PConjConj : Conj -> PConj ;
+-- There are also 'one-word utterances'. A typical use of them is
+-- as answers to questions.
+-- *Note*. This list is incomplete. More categories could be covered.
+-- Moreover, in many languages e.g. noun phrases in different cases
+-- can be used.
+
+    UttIP   : IP   -> Utt ;                 -- who
+    UttIAdv : IAdv -> Utt ;                 -- why
+    UttNP   : NP   -> Utt ;                 -- this man
+    UttAdv  : Adv  -> Utt ;                 -- here
+    UttVP   : VP   -> Utt ;                 -- to sleep
+
+-- The phrasal conjunction is optional. A sentence conjunction
+-- can also used to prefix an utterance.
+
+    NoPConj   : PConj ;                      
+    PConjConj : Conj -> PConj ;             -- and
+
+-- The vocative is optional. Any noun phrase can be made into vocative,
+-- which may be overgenerating (e.g. "I").
 
     NoVoc   : Voc ;
-    VocNP   : NP -> Voc ;
+    VocNP   : NP -> Voc ;                   -- my friend
+
 }

lib/resource-1.0/abstract/Sentence.gf

@@ -1,19 +1,53 @@
+--1 Clauses, imperatives, and sentential complements
+
 abstract Sentence = Cat ** {
 
+--2 Clauses
+
+-- The $NP VP$ predication rule form a clause whose linearization
+-- gives a table of all tense variants, positive and negative.
+-- Clauses are converted to $S$ (with fixed tense) in [Tensed Tensed.html].
+
   fun
+    PredVP    : NP -> VP -> Cl ;         -- John walks
 
-    PredVP   : NP -> VP -> Cl ;
-    PredSCVP : SC -> VP -> Cl ;
+-- Using an embedded sentence as a subject is treated separately.
+-- This can be overgenerating. E.g. "whether you go" as subject
+-- is only meaningful for some verb phrases.
 
-    ImpVP    : VP -> Imp ;
+    PredSCVP  : SC -> VP -> Cl ;         -- that you go makes me happy
 
-    SlashV2   : NP -> V2 -> Slash ;
-    SlashVVV2 : NP -> VV -> V2 -> Slash ;
-    AdvSlash  : Slash -> Adv -> Slash ;
-    SlashPrep : Cl -> Prep -> Slash ;
+--2 Clauses missing object noun phrases
+
+-- This category is a variant of the 'slash category' $S/NP$ of
+-- GPSG and categorial grammars, which in turn replaces
+-- movement transformations in the formation of questions
+-- and relative clauses. Except $SlashV2$, the construction 
+-- rules can be seen as special cases of function composition, in
+-- the style of CCG.
+-- *Note* the set is not complete and lacks e.g. verbs with more than 2 places.
+
+    SlashV2   : NP -> V2 -> Slash ;      -- (whom) he sees
+    SlashVVV2 : NP -> VV -> V2 -> Slash; -- (whom) he wants to see 
+    AdvSlash  : Slash -> Adv -> Slash ;  -- (whom) he sees tomorrow
+    SlashPrep : Cl -> Prep -> Slash ;    -- (with whom) he walks 
+
+--2 Imperatives
+
+-- An imperative is straightforwardly formed from a verb phrase.
+-- It has variation over positive and negative, singular and plural.
+-- To fix these parameters, see [Phrase Phrase.html].
+
+    ImpVP     : VP -> Imp ;              -- go
+
+--2 Embedded sentences
+
+-- Sentences, questions, and infinitival phrases can be used as
+-- subjects and (adverbial) complements.
+
+    EmbedS    : S  -> SC ;               -- that you go
+    EmbedQS   : QS -> SC ;               -- whether you go
+    EmbedVP   : VP -> SC ;               -- to go
 
-    EmbedS  : S  -> SC ;
-    EmbedQS : QS -> SC ;
-    EmbedVP : VP -> SC ;
 
 }