Index: trunk/src/org/openstreetmap/josm/corrector/TagCorrector.java
===================================================================
--- trunk/src/org/openstreetmap/josm/corrector/TagCorrector.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/corrector/TagCorrector.java	(revision 2853)
@@ -41,5 +41,5 @@
     private String[] applicationOptions = new String[] {
             tr("Apply selected changes"),
-            tr("Don't apply changes"),
+            tr("Do not apply changes"),
             tr("Cancel")
     };
Index: trunk/src/org/openstreetmap/josm/plugins/PluginDownloadTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/plugins/PluginDownloadTask.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/plugins/PluginDownloadTask.java	(revision 2853)
@@ -103,5 +103,5 @@
         try {
             if (pi.downloadlink == null) {
-                String msg = tr("Warning: Cannot download plugin ''{0}''. Its download link isn''t known. Skipping download.", pi.name);
+                String msg = tr("Warning: Cannot download plugin ''{0}''. Its download link is not known. Skipping download.", pi.name);
                 System.err.println(msg);
                 throw new PluginDownloadException(msg);
@@ -124,5 +124,5 @@
             in.close();
         } catch(MalformedURLException e) {
-            String msg = tr("Warning: Cannot download plugin ''{0}''. Its download link ''{1}'' isn''t a valid URL. Skipping download.", pi.name, pi.downloadlink);
+            String msg = tr("Warning: Cannot download plugin ''{0}''. Its download link ''{1}'' is not a valid URL. Skipping download.", pi.name, pi.downloadlink);
             System.err.println(msg);
             throw new PluginDownloadException(msg);
Index: trunk/src/org/openstreetmap/josm/plugins/PluginHandler.java
===================================================================
--- trunk/src/org/openstreetmap/josm/plugins/PluginHandler.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/plugins/PluginHandler.java	(revision 2853)
@@ -131,5 +131,5 @@
                 continue;
             }
-            String msg =  tr("<html>Loading of {0} plugin was requested."
+            String msg =  tr("<html>Loading of the plugin \"{0}\" was requested."
                     + "<br>This plugin is no longer developed and very likely will produce errors."
                     +"<br>It should be disabled.<br>Delete from preferences?</html>", unmaintained);
@@ -200,6 +200,6 @@
         StringBuilder sb = new StringBuilder();
         sb.append("<html>");
-        sb.append(trn("A required plugin for plugin {0} was not found. The required plugin is:",
-                "{1} required plugins for plugin {0} were not found. The required plugins are:",
+        sb.append(trn("A required plugin for plugin {0} was not found. The missing plugin is:",
+                "{1} required plugins for plugin {0} were not found. The missing plugins are:",
                 missingRequiredPlugin.size(),
                 plugin,
@@ -691,5 +691,5 @@
             dialog.setButtonIcons(new String[] {"dialogs/delete.png", "cancel.png"});
             dialog.setContent(
-                    tr("<html>") +
+                    "<html>" +
                     tr("An unexpected exception occurred that may have come from the ''{0}'' plugin.", plugin.getPluginInformation().name)
                     + "<br>"
Index: trunk/src/org/openstreetmap/josm/plugins/PluginInformation.java
===================================================================
--- trunk/src/org/openstreetmap/josm/plugins/PluginInformation.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/plugins/PluginInformation.java	(revision 2853)
@@ -67,5 +67,5 @@
             Manifest manifest = jar.getManifest();
             if (manifest == null)
-                throw new PluginException(name, tr("The plugin file ''{0}'' doesn't include a Manifest.", file.toString()));
+                throw new PluginException(name, tr("The plugin file ''{0}'' does not include a Manifest.", file.toString()));
             scanManifest(manifest, false);
             libraries.add(0, fileToURL(file));
Index: trunk/src/org/openstreetmap/josm/tools/BugReportExceptionHandler.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/BugReportExceptionHandler.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/tools/BugReportExceptionHandler.java	(revision 2853)
@@ -113,5 +113,5 @@
                             "the error and try to supply as much detail as possible.")), GBC.eop());
                     p.add(new JMultilineLabel(
-                            tr("Alternatively, if that doesn't work you can manually fill in the information" +
+                            tr("Alternatively, if that does not work you can manually fill in the information" +
                             "below at this URL:")), GBC.eol());
                     p.add(new UrlLabel("http://josm.openstreetmap.de/newticket"), GBC.eop().insets(8,0,0,0));
Index: trunk/src/org/openstreetmap/josm/tools/CheckParameterUtil.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/CheckParameterUtil.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/tools/CheckParameterUtil.java	(revision 2853)
@@ -2,5 +2,5 @@
 package org.openstreetmap.josm.tools;
 
-import static org.openstreetmap.josm.tools.I18n.tr;
+import java.text.MessageFormat;
 
 import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
@@ -17,18 +17,17 @@
 
     public static void ensureValidPrimitiveId(PrimitiveId id, String parameterName) throws IllegalArgumentException {
-        if (id == null)
-            throw new IllegalArgumentException(tr("Parameter ''{0}'' must not be null", parameterName));
+        ensureParameterNotNull(id, parameterName);
         if (id.getUniqueId() <= 0)
-            throw new IllegalArgumentException(tr("Expected unique id > 0 for primitive id, got {0}", id.getUniqueId()));
+            throw new IllegalArgumentException(MessageFormat.format("Expected unique id > 0 for primitive ''{1}'', got {0}", id.getUniqueId(), parameterName));
     }
 
     public static void ensureValidVersion(long version, String parameterName) throws IllegalArgumentException {
         if (version < 0)
-            throw new IllegalArgumentException(tr("Expected value of type long > 0 for parameter ''{0}'', got {1}", parameterName, version));
+            throw new IllegalArgumentException(MessageFormat.format("Expected value of type long > 0 for parameter ''{0}'', got {1}", parameterName, version));
     }
 
     public static void ensureParameterNotNull(Object value, String parameterName) {
         if (value == null)
-            throw new IllegalArgumentException(tr("Parameter ''{0}'' must not be null", parameterName));
+            throw new IllegalArgumentException(MessageFormat.format("Parameter ''{0}'' must not be null", parameterName));
     }
 
@@ -42,8 +41,7 @@
      */
     public static void ensureValidNodeId(PrimitiveId id, String parameterName) throws IllegalArgumentException {
-        if (id == null)
-            throw new IllegalArgumentException(tr("Parameter ''{0}'' must not be null", parameterName));
+        ensureParameterNotNull(id, parameterName);
         if (! id.getType().equals(OsmPrimitiveType.NODE))
-            throw new IllegalArgumentException(tr("Parameter ''{0}'' of type node expected, got ''{1}''", parameterName, id.getType().getAPIName()));
+            throw new IllegalArgumentException(MessageFormat.format("Parameter ''{0}'' of type node expected, got ''{1}''", parameterName, id.getType().getAPIName()));
     }
 }
Index: trunk/src/org/openstreetmap/josm/tools/ExceptionUtil.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/ExceptionUtil.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/tools/ExceptionUtil.java	(revision 2853)
@@ -224,5 +224,5 @@
         String message = tr("<html>Failed to open a connection to the remote server<br>" + "''{0}''<br>"
                 + "for security reasons. This is most likely because you are running<br>"
-                + "in an applet and because you didn''t load your applet from ''{1}''.</html>", apiUrl, host);
+                + "in an applet and because you did not load your applet from ''{1}''.</html>", apiUrl, host);
         return message;
     }
@@ -305,8 +305,8 @@
     public static String explainNotFound(OsmApiException e) {
         String apiUrl = OsmApi.getOsmApi().getBaseUrl();
-        String message = tr("The OSM server ''{0}'' doesn''t know about an object<br>"
+        String message = tr("The OSM server ''{0}'' does not know about an object<br>"
                 + "you tried to read, update, or delete. Either the respective object<br>"
-                + "doesn''t exist on the server or you''re using an invalid URL to access<br>"
-                + "it. Please carefully check the servers address ''{0}'' for typos."
+                + "does not exist on the server or you are using an invalid URL to access<br>"
+                + "it. Please carefully check the server''s address ''{0}'' for typos."
                 , apiUrl);
         message = "<html>" + message + "</html>";
@@ -333,5 +333,5 @@
 
         String message = tr("<html>Failed to open a connection to the remote server<br>" + "''{0}''.<br>"
-                + "Host name ''{1}'' couldn''t be resolved. <br>"
+                + "Host name ''{1}'' could not be resolved. <br>"
                 + "Please check the API URL in your preferences and your internet connection.</html>", apiUrl, host);
         e.printStackTrace();
Index: trunk/src/org/openstreetmap/josm/tools/ImageProvider.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/ImageProvider.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/tools/ImageProvider.java	(revision 2853)
@@ -340,6 +340,5 @@
      */
     public static ImageIcon get(OsmPrimitiveType type) throws IllegalArgumentException {
-        if (type == null)
-            throw new IllegalArgumentException(tr("Parameter ''{0}'' must not be null.", "type"));
+        CheckParameterUtil.ensureParameterNotNull(type, "type");
         return get("data", type.getAPIName());
     }
Index: trunk/src/org/openstreetmap/josm/tools/WindowGeometry.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/WindowGeometry.java	(revision 2852)
+++ trunk/src/org/openstreetmap/josm/tools/WindowGeometry.java	(revision 2853)
@@ -105,5 +105,5 @@
             Matcher m = p.matcher(preferenceValue);
             if (!m.find())
-                throw new WindowGeometryException(tr("Preference with key ''{0}'' does not include ''{1}''. Can''t restore window geometry from preferences.", preferenceKey, field));
+                throw new WindowGeometryException(tr("Preference with key ''{0}'' does not include ''{1}''. Cannot restore window geometry from preferences.", preferenceKey, field));
             v = m.group(1);
             return Integer.parseInt(v);
@@ -111,7 +111,7 @@
             throw e;
         } catch(NumberFormatException e) {
-            throw new WindowGeometryException(tr("Preference with key ''{0}'' does not provide an int value for ''{1}''. Got {2}. Can''t restore window geometry from preferences.", preferenceKey, field, v));
+            throw new WindowGeometryException(tr("Preference with key ''{0}'' does not provide an int value for ''{1}''. Got {2}. Cannot restore window geometry from preferences.", preferenceKey, field, v));
         } catch(Exception e) {
-            throw new WindowGeometryException(tr("Failed to parse field ''{1}'' in preference with key ''{0}''. Exception was: {2}. Can''t restore window geometry from preferences.", preferenceKey, field, e.toString()), e);
+            throw new WindowGeometryException(tr("Failed to parse field ''{1}'' in preference with key ''{0}''. Exception was: {2}. Cannot restore window geometry from preferences.", preferenceKey, field, e.toString()), e);
         }
     }
@@ -120,5 +120,5 @@
         String value = Main.pref.get(preferenceKey);
         if (value == null || value.equals(""))
-            throw new WindowGeometryException(tr("Preference with key ''{0}'' does not exist. Can''t restore window geometry from preferences.", preferenceKey));
+            throw new WindowGeometryException(tr("Preference with key ''{0}'' does not exist. Cannot restore window geometry from preferences.", preferenceKey));
         topLeft = new Point();
         extent = new Dimension();
