diff --git a/pattern/text/es/inflect.py b/pattern/text/es/inflect.py
index 16cd6228..c0c9bb45 100644
--- a/pattern/text/es/inflect.py
+++ b/pattern/text/es/inflect.py
@@ -170,7 +170,7 @@ def singularize(word, pos=NOUN, custom={}):
             return "un"
         return w
     # hombres => hombre
-    if w.endswith("es") and w[:-2].endswith(("br", "i", "j", "t", "zn")):
+    if w.endswith("es") and w[:-2].endswith(("br", "i", "j", "t", "zn", "rr", "gr", "rn", "v", "f", "m", "qu", "gu", "g", "ch", "p")):
         return w[:-1]
     # gestiones => gestión
     for a, b in (
@@ -421,4 +421,4 @@ def predicative(adjective):
         if len(w) >= 4 and not is_vowel(normalize(w[-3])) and not is_vowel(normalize(w[-4])):
             return w[:-1]
         return w[:-2]
-    return w
\ No newline at end of file
+    return w