compound: rewrite (#989)

_u-dep/compound.md

@@ -5,11 +5,27 @@ shortdef: 'compound'
 udver: '2'
 ---
 
-The `compound` relation is one of three relations for multiword expressions (MWEs) (the other two being `fixed` and `flat`). It is used
+The compound relation is used to analyze compounds, that is, combinations of lexemes that morphosyntactically behave as single words. Commonly occurring cases are:
 
-- for any kind of X<sup>0</sup> compounding: noun compounds (e.g., *phone book*), but also verb and
-adjective compounds that are more common in other languages (such as Persian or Japanese light verb constructions).
-See further discussion at [Two Nominals](/workgroups/newdoc/two_nominals.html).
+- Nominal compounds written as separate words, for example English _<b>apple juice</b>_.
+- Particle verbs where the particle is realized as a separate word (which may alternate with affixed particles), for example Swedish _<b>byta ut</b>_ ('exchange'; cf. _<b>utbytt</b>_, 'exchanged'). The subtype [compound:prt]() is commonly used in this case.
+- Serial verbs, for which the subtype [compound:svc]() is commonly used, as in this Nupe example [(Tallerman 2014)](https://doi.org/10.4324/9780429243592):
+
+~~~ sdparse
+Musa bé lá èbi \n Musa came took knife \n Musa came to take the knife
+nsubj(bé, Musa)
+compound:svc(bé, lá)
+obj(bé, èbi)
+~~~
+
+Each language that uses `compound` should develop its own specific criteria based on morphosyntax (rather than lexicalization or semantic idiomaticity), though elsewhere the term “compound” may be used more broadly.
+
+**See also:**
+- [Two Nominals working group](/workgroups/newdoc/two_nominals.html).
+- [Expletive reflexives](/u/dep/expl.html#reflexives)
+
+
+## English Examples
 
 ~~~ sdparse
 phone book
@@ -32,28 +48,15 @@ Sam took out a $ 3 million loan
 compound(loan, $)
 ~~~
 
-- for particle verbs (with the subtype [compound:prt]()):
-
 ~~~ sdparse
 put up
 compound:prt(put, up)
 ~~~
 
-- for serial verbs (with the subtype [compound:svc]()):
+### Not `compound`
 
-~~~ sdparse
-Musa bé lá èbi \n Musa came took knife
-nsubj(bé, Musa)
-compound:svc(bé, lá)
-obj(bé, èbi)
-~~~
-
-The `compound` relation (nor any subtype thereof) is not used to link an inherently reflexive verb with the reflexive morpheme, despite the similarity of this construction to particle verbs. The current UD guideline is to use an appropriate [subtype](/u/dep/expl.html#reflexives) of the [expl]() relation.
-
-Each language that uses `compound` should develop its own specific criteria based on morphosyntax (rather than lexicalization or semantic idiomaticity),
-though elsewhere the terms "compound" and "multiword expression" may be used more broadly.
-In English, for example, adjective-noun combinations, prepositional phrases, and light verb constructions are better described
-with other relations:
+Just because an expression is lexicalized or idiomatic does not mean `compound` applies.
+In English, adjective-noun combinations, prepositional phrases, and light verb constructions are better described with other relations:
 
 ~~~ sdparse
 hot dog
@@ -73,4 +76,5 @@ obj(make, decision)
 det(decision, a)
 ~~~
 
+
 <!-- Interlanguage links updated Út 9. května 2023, 20:04:05 CEST -->