diff --git a/dictsource/lv_rules b/dictsource/lv_rules
index 1960eb27..2ed3f724 100644
--- a/dictsource/lv_rules
+++ b/dictsource/lv_rules
@@ -56,6 +56,7 @@
 // +---------------------------+
 // |     Pronunciation of o    |
 // +---------------------------+
+.L30  ō ó                              // uo pre/post fixes. If facultative writing is used, o is spelled as uo
 
 // Default rules for o with succeeding consonants
 .L40  č ģ ķ ļ ņ ŗ š ž                  // uo indicators — o is spelled as uo in words with Latvian soft consonants
@@ -466,6 +467,25 @@ L41L10L10L10L10L10)               o (<<<<<      o
            o (L10L41                            o
            o (L41+                              o
 
+                                     // uo indicators before (facultative writing)
+L30L10L10L10L10L10L10L10)         o (<<<<<<<    uo
+L30L10L10L10L10L10L10)            o (<<<<<<     uo
+L30L10L10L10L10L10)               o (<<<<<      uo
+   L30L10L10L10L10)               o (<<<<       uo
+     L30L10L10L10)                o (<<<        uo
+        L30L10L10)                o (<<         uo
+           L30L10)                o (<          uo
+              L30)                o             uo
+                                     // uo indicators after (facultative writing)
+           o (L10L10L10L10L10L10L30<<<<<        uo
+           o (L10L10L10L10L10L30<<<<            uo
+           o (L10L10L10L10L30<<<                uo
+           o (L10L10L10L30<<                    uo
+           o (L10L10L30<                        uo
+           o (L10L30                            uo
+           o (L30+                              uo
+
+
            o               uo        // words with Latvian roots are more common
            o (_++          uo        // common ending for Latvian words
            o (L40          uo        // usually uo before soft (Latvian) consonants
@@ -1464,6 +1484,9 @@ L41L10L10L10sk) o (pL01_   o:        //  ...skops
 .group ō
            ō               o:
 
+.group ó
+           ó               o         // short o
+
 .group p
            p               p
                                      // pus..number stress on next syllable