diff --git a/lib/src/abstract/Sentence.gf b/lib/src/abstract/Sentence.gf
index 12283d70b..f7c30235b 100644
--- a/lib/src/abstract/Sentence.gf
+++ b/lib/src/abstract/Sentence.gf
@@ -62,9 +62,11 @@ abstract Sentence = Cat ** {
     UseRCl   : Temp -> Pol -> RCl -> RS ;
     UseSlash : Temp -> Pol -> ClSlash -> SSlash ;
 
--- An adverb can be added to the beginning of a sentence.
+-- An adverb can be added to the beginning of a sentence, either with comma ("externally")
+-- or without:
 
-    AdvS     : Adv -> S  -> S ;            -- today, I will go home
+    AdvS     : Adv -> S  -> S ;            -- then I will go home
+    ExtAdvS  : Adv -> S  -> S ;            -- next week, I will go home
 
 -- This covers subjunctive clauses, but they can also be added to the end.
 
diff --git a/lib/src/english/SentenceEng.gf b/lib/src/english/SentenceEng.gf
index 00d2405a9..dbd482cc8 100644
--- a/lib/src/english/SentenceEng.gf
+++ b/lib/src/english/SentenceEng.gf
@@ -56,7 +56,8 @@ concrete SentenceEng of Sentence = CatEng ** open Prelude, ResEng in {
       c2 = cl.c2
     } ;
 
-    AdvS a s = {s = a.s ++ "," ++ s.s} ;
+    AdvS a s = {s = a.s ++ s.s} ;
+    ExtAdvS a s = {s = a.s ++ "," ++ s.s} ;
 
     SSubjS a s b = {s = a.s ++ s.s ++ b.s} ;
 
diff --git a/lib/src/finnish/SentenceFin.gf b/lib/src/finnish/SentenceFin.gf
index 010321f78..1f2fc2fee 100644
--- a/lib/src/finnish/SentenceFin.gf
+++ b/lib/src/finnish/SentenceFin.gf
@@ -60,6 +60,7 @@ concrete SentenceFin of Sentence = CatFin ** open Prelude, ResFin in {
     } ;
 
     AdvS a s = {s = a.s ++ s.s} ;
+    ExtAdvS a s = {s = a.s ++ "," ++ s.s} ;
 
     RelS s r = {s = s.s ++ "," ++ r.s ! agrP3 Sg} ; ---- mikä
 
diff --git a/lib/src/german/SentenceGer.gf b/lib/src/german/SentenceGer.gf
index 6e13c97d1..2cfc0343d 100644
--- a/lib/src/german/SentenceGer.gf
+++ b/lib/src/german/SentenceGer.gf
@@ -61,6 +61,8 @@ concrete SentenceGer of Sentence = CatGer ** open ResGer, Prelude in {
       } ;
 
     AdvS a s = {s = table {Sub => a.s ++ s.s ! Sub ; o => a.s ++ s.s ! Inv}} ;
+    ExtAdvS a s = 
+      {s = table {Sub => a.s ++ "," ++ s.s ! Sub ; o => a.s ++ "," ++ s.s ! Inv}} ;
 
     SSubjS a s b = {s = \\o => a.s ! o ++ "," ++ s.s ++ b.s ! Sub} ;
 
diff --git a/lib/src/romance/SentenceRomance.gf b/lib/src/romance/SentenceRomance.gf
index 4bb394119..24f27f085 100644
--- a/lib/src/romance/SentenceRomance.gf
+++ b/lib/src/romance/SentenceRomance.gf
@@ -67,7 +67,8 @@ incomplete concrete SentenceRomance of Sentence =
       c2 = cl.c2
     } ;
 
-    AdvS a s = {s = \\o => a.s ++ "," ++ s.s ! o} ;
+    AdvS a s = {s = \\o => a.s ++ s.s ! o} ;
+    ExtAdvS a s = {s = \\o => a.s ++ "," ++ s.s ! o} ;
 
     SSubjS a s b = {s = \\m => a.s ! m ++ s.s ++ b.s ! s.m} ;
 
diff --git a/lib/src/scandinavian/SentenceScand.gf b/lib/src/scandinavian/SentenceScand.gf
index 0be938cbb..31e235eb4 100644
--- a/lib/src/scandinavian/SentenceScand.gf
+++ b/lib/src/scandinavian/SentenceScand.gf
@@ -58,6 +58,7 @@ incomplete concrete SentenceScand of Sentence =
     } ;
 
     AdvS a s = {s = \\o => a.s ++ s.s ! Inv} ;
+    ExtAdvS a s = {s = \\o => a.s ++ "," ++ s.s ! Inv} ;
 
     RelS s r = {s = \\o => s.s ! o ++ "," ++ r.s ! agrP3 Neutr Sg} ; --- vilket