diff --git a/lib/recase/cases/name_case.ex b/lib/recase/cases/name_case.ex
index a4202f0..ce17586 100644
--- a/lib/recase/cases/name_case.ex
+++ b/lib/recase/cases/name_case.ex
@@ -25,29 +25,31 @@ defmodule Recase.NameCase do
       String.downcase(apostophe_ess)
     end)
     |> replace_irish()
-    |> replace(~r|\bVon\b|u, "von")
+    |> replace(~r|\bVon(?=\s+\w)|u, "von")
     |> replace(~r|\bVan(?=\s+\w)|u, "van")
-    |> replace(~r|\bAp\b|u, "ap")
+    |> replace(~r|\bAp(?=\s+\w)|u, "ap")
     |> replace(~r|\bAl(?=\s+\w)|u, "al")
-    |> replace(~r|\bEl\b|u, "el")
-    |> replace(~r|\bLa\b|u, "la")
+    |> replace(~r|\bEl(?=\s+\w)|u, "el")
+    |> replace(~r|\bLa(?=\s+\w)|u, "la")
     |> replace(~r|\bBen(?=\s+\w)|u, "ben")
-    |> replace(~r/\b(Bin|Binti|Binte)\b/u, fn bin_prefix ->
+    |> replace(~r/\b(Bin|Binti|Binte)(?=\s+\w)/u, fn bin_prefix ->
       String.downcase(bin_prefix)
     end)
-    |> replace(~r|\bD([aeiou])\b|u, fn da_prefix ->
+    |> replace(~r|\bD([aeiou])(?=\s+\w)|u, fn da_prefix ->
       String.downcase(da_prefix)
     end)
-    |> replace(~r|\bD([ao]s)\b|u, fn das_prefix ->
+    |> replace(~r|\bD([ao]s)(?=\s+\w)|u, fn das_prefix ->
       String.downcase(das_prefix)
     end)
-    |> replace(~r|\bDell([ae])\b|u, fn dell_prefix ->
+    |> replace(~r|\bDell([ae])(?=\s+\w)|u, fn dell_prefix ->
       String.downcase(dell_prefix)
     end)
-    |> replace(~r|\bDe([lr])\b|u, fn del_prefix ->
+    |> replace(~r|\bDe([lr])(?=\s+\w)|u, fn del_prefix ->
       String.downcase(del_prefix)
     end)
-    |> replace(~r|\bL([eo])\b|u, fn le_prefix -> String.downcase(le_prefix) end)
+    |> replace(~r|\bL([eo])(?=\s+\w)|u, fn le_prefix ->
+      String.downcase(le_prefix)
+    end)
     |> replace_roman_numerals()
     |> replace(~r|\b([YEI])\b|u, fn conjunction ->
       String.downcase(conjunction)
diff --git a/test/recase_test/name_case_test.exs b/test/recase_test/name_case_test.exs
index 6a4f596..e1acdbb 100644
--- a/test/recase_test/name_case_test.exs
+++ b/test/recase_test/name_case_test.exs
@@ -18,21 +18,34 @@ defmodule Recase.NameCaseTest do
     assert convert("al fahd") == "al Fahd"
     assert convert("al") == "Al"
     assert convert("el grecco") == "el Grecco"
+    assert convert("el") == "El"
     assert convert("bin friendly") == "bin Friendly"
+    assert convert("bin") == "Bin"
     assert convert("ben gurion") == "ben Gurion"
     assert convert("ben") == "Ben"
     assert convert("dos brasileiros") == "dos Brasileiros"
+    assert convert("dos") == "Dos"
     assert convert("da vinci") == "da Vinci"
+    assert convert("da") == "Da"
     assert convert("di caprio") == "di Caprio"
+    assert convert("di") == "Di"
     assert convert("du pont") == "du Pont"
+    assert convert("du") == "Du"
     assert convert("de legate") == "de Legate"
+    assert convert("de") == "De"
     assert convert("del crond") == "del Crond"
+    assert convert("del") == "Del"
     assert convert("della crond") == "della Crond"
+    assert convert("della") == "Della"
     assert convert("der sind") == "der Sind"
+    assert convert("der") == "Der"
     assert convert("van der Post") == "van der Post"
     assert convert("von trapp") == "von Trapp"
+    assert convert("von") == "Von"
     assert convert("la poisson") == "la Poisson"
+    assert convert("la") == "La"
     assert convert("le figaro") == "le Figaro"
+    assert convert("le") == "Le"
     assert convert("mack knife") == "Mack Knife"
     assert convert("dougal macdonald") == "Dougal MacDonald"
     assert convert("ruiz y picasso") == "Ruiz y Picasso"