diff --git a/src/applications/almanac/management/AlmanacManagementRegisterWorkflow.php b/src/applications/almanac/management/AlmanacManagementRegisterWorkflow.php
--- a/src/applications/almanac/management/AlmanacManagementRegisterWorkflow.php
+++ b/src/applications/almanac/management/AlmanacManagementRegisterWorkflow.php
@@ -192,7 +192,7 @@
 
     $console->writeOut(
       "%s\n",
-      pht('Installing device ID...', $raw_device));
+      pht('Installing device %s...', $raw_device));
 
     // The permissions on this file are more open because the webserver also
     // needs to read it.
diff --git a/src/applications/conduit/protocol/exception/ConduitMethodDoesNotExistException.php b/src/applications/conduit/protocol/exception/ConduitMethodDoesNotExistException.php
--- a/src/applications/conduit/protocol/exception/ConduitMethodDoesNotExistException.php
+++ b/src/applications/conduit/protocol/exception/ConduitMethodDoesNotExistException.php
@@ -6,7 +6,8 @@
   public function __construct($method_name) {
     parent::__construct(
       pht(
-        'Conduit API method "%s" does not exist.'));
+        'Conduit API method "%s" does not exist.',
+        $method_name));
   }
 
 }
diff --git a/src/applications/config/view/PhabricatorSetupIssueView.php b/src/applications/config/view/PhabricatorSetupIssueView.php
--- a/src/applications/config/view/PhabricatorSetupIssueView.php
+++ b/src/applications/config/view/PhabricatorSetupIssueView.php
@@ -385,8 +385,8 @@
         'p',
         array(),
         pht(
-          'PHP also loaded these configuration file(s):',
-          count($more_loc)));
+          'PHP also loaded these %s configuration file(s):',
+          new PhutilNumber(count($more_loc))));
       $info[] = phutil_tag(
         'pre',
         array(),
diff --git a/src/applications/differential/event/DifferentialHovercardEventListener.php b/src/applications/differential/event/DifferentialHovercardEventListener.php
--- a/src/applications/differential/event/DifferentialHovercardEventListener.php
+++ b/src/applications/differential/event/DifferentialHovercardEventListener.php
@@ -60,7 +60,7 @@
       implode_selected_handle_links(', ', $handles, $reviewer_phids));
 
     if ($tasks) {
-      $hovercard->addField(pht('Task(s)', count($tasks)),
+      $hovercard->addField(pht('%s Task(s)', new PhutilNumber(count($tasks))),
         implode_selected_handle_links(', ', $handles, $tasks));
     }
 
diff --git a/src/applications/differential/mail/DifferentialCreateMailReceiver.php b/src/applications/differential/mail/DifferentialCreateMailReceiver.php
--- a/src/applications/differential/mail/DifferentialCreateMailReceiver.php
+++ b/src/applications/differential/mail/DifferentialCreateMailReceiver.php
@@ -79,15 +79,15 @@
         count($diffs));
     } else {
       $subject = pht(
-        'Diff creation failed; see body for error(s).',
-        count($errors));
+        'Diff creation failed; see body for %s error(s).',
+        new PhutilNumber(count($errors)));
     }
     $body = new PhabricatorMetaMTAMailBody();
     $body->addRawSection($subject);
     if (count($diffs)) {
       $text_body = '';
       $html_body = array();
-      $body_label = pht('DIFF LINK(S)', count($diffs));
+      $body_label = pht('%s DIFF LINK(S)', new PhutilNumber(count($diffs)));
       foreach ($diffs as $filename => $diff_uri) {
         $text_body .= $filename.': '.$diff_uri."\n";
         $html_body[] = phutil_tag(
@@ -104,7 +104,7 @@
 
     if (count($errors)) {
       $body_section = new PhabricatorMetaMTAMailSection();
-      $body_label = pht('ERROR(S)', count($errors));
+      $body_label = pht('%s ERROR(S)', new PhutilNumber(count($errors)));
       foreach ($errors as $error) {
         $body_section->addFragment($error);
       }
diff --git a/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php b/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
--- a/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
+++ b/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
@@ -10,40 +10,27 @@
     $file = $changeset->getFileType();
 
     $messages = array();
-    $none = hsprintf('');
     switch ($change) {
 
       case DifferentialChangeType::TYPE_ADD:
         switch ($file) {
           case DifferentialChangeType::FILE_TEXT:
-            $messages[] = pht(
-              'This file was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This file was added.');
             break;
           case DifferentialChangeType::FILE_IMAGE:
-            $messages[] = pht(
-              'This image was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This image was added.');
             break;
           case DifferentialChangeType::FILE_DIRECTORY:
-            $messages[] = pht(
-              'This directory was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This directory was added.');
             break;
           case DifferentialChangeType::FILE_BINARY:
-            $messages[] = pht(
-              'This binary file was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This binary file was added.');
             break;
           case DifferentialChangeType::FILE_SYMLINK:
-            $messages[] = pht(
-              'This symlink was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This symlink was added.');
             break;
           case DifferentialChangeType::FILE_SUBMODULE:
-            $messages[] = pht(
-              'This submodule was <strong>added</strong>.',
-              $none);
+            $messages[] = pht('This submodule was added.');
             break;
         }
         break;
@@ -51,34 +38,22 @@
       case DifferentialChangeType::TYPE_DELETE:
         switch ($file) {
           case DifferentialChangeType::FILE_TEXT:
-            $messages[] = pht(
-              'This file was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This file was deleted.');
             break;
           case DifferentialChangeType::FILE_IMAGE:
-            $messages[] = pht(
-              'This image was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This image was deleted.');
             break;
           case DifferentialChangeType::FILE_DIRECTORY:
-            $messages[] = pht(
-              'This directory was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This directory was deleted.');
             break;
           case DifferentialChangeType::FILE_BINARY:
-            $messages[] = pht(
-              'This binary file was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This binary file was deleted.');
             break;
           case DifferentialChangeType::FILE_SYMLINK:
-            $messages[] = pht(
-              'This symlink was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This symlink was deleted.');
             break;
           case DifferentialChangeType::FILE_SUBMODULE:
-            $messages[] = pht(
-              'This submodule was <strong>deleted</strong>.',
-              $none);
+            $messages[] = pht('This submodule was deleted.');
             break;
         }
         break;
diff --git a/src/applications/people/controller/PhabricatorPeopleApproveController.php b/src/applications/people/controller/PhabricatorPeopleApproveController.php
--- a/src/applications/people/controller/PhabricatorPeopleApproveController.php
+++ b/src/applications/people/controller/PhabricatorPeopleApproveController.php
@@ -31,8 +31,7 @@
 
       $title = pht(
         'Phabricator Account "%s" Approved',
-        $user->getUsername(),
-        $admin->getUsername());
+        $user->getUsername());
 
       $body = pht(
         "Your Phabricator account (%s) has been approved by %s. You can ".
diff --git a/src/applications/repository/data/PhabricatorRepositoryURINormalizer.php b/src/applications/repository/data/PhabricatorRepositoryURINormalizer.php
--- a/src/applications/repository/data/PhabricatorRepositoryURINormalizer.php
+++ b/src/applications/repository/data/PhabricatorRepositoryURINormalizer.php
@@ -52,7 +52,7 @@
       case self::TYPE_MERCURIAL:
         break;
       default:
-        throw new Exception(pht('Unknown URI type "%s"!'));
+        throw new Exception(pht('Unknown URI type "%s"!', $type));
     }
 
     $this->type = $type;
diff --git a/src/applications/repository/management/PhabricatorRepositoryManagementLookupUsersWorkflow.php b/src/applications/repository/management/PhabricatorRepositoryManagementLookupUsersWorkflow.php
--- a/src/applications/repository/management/PhabricatorRepositoryManagementLookupUsersWorkflow.php
+++ b/src/applications/repository/management/PhabricatorRepositoryManagementLookupUsersWorkflow.php
@@ -48,7 +48,9 @@
 
       if (empty($refs_raw['data'])) {
         throw new Exception(
-          pht('Unable to retrieve details for commit "%s"!'));
+          pht(
+            'Unable to retrieve details for commit "%s"!',
+            $commit->getPHID()));
       }
 
       $ref = DiffusionCommitRef::newFromConduitResult(head($refs_raw['data']));
diff --git a/src/infrastructure/internationalization/translation/PhabricatorBaseEnglishTranslation.php b/src/infrastructure/internationalization/translation/PhabricatorBaseEnglishTranslation.php
--- a/src/infrastructure/internationalization/translation/PhabricatorBaseEnglishTranslation.php
+++ b/src/infrastructure/internationalization/translation/PhabricatorBaseEnglishTranslation.php
@@ -17,9 +17,9 @@
         'This configuration value is related:',
         'These configuration values are related:',
       ),
-      'Task(s)' => array('Task', 'Tasks'),
+      '%s Task(s)' => array('Task', 'Tasks'),
 
-      'ERROR(S)' => array('ERROR', 'ERRORS'),
+      '%s ERROR(S)' => array('ERROR', 'ERRORS'),
       '%d Error(s)' => array('%d Error', '%d Errors'),
       '%d Warning(s)' => array('%d Warning', '%d Warnings'),
       '%d Auto-Fix(es)' => array('%d Auto-Fix', '%d Auto-Fixes'),
@@ -32,12 +32,12 @@
       '%d path(s)' => array('%d path', '%d paths'),
       '%d diff(s)' => array('%d diff', '%d diffs'),
 
-      'DIFF LINK(S)' => array('DIFF LINK', 'DIFF LINKS'),
+      '%s DIFF LINK(S)' => array('DIFF LINK', 'DIFF LINKS'),
       'You successfully created %d diff(s).' => array(
         'You successfully created %d diff.',
         'You successfully created %d diffs.',
       ),
-      'Diff creation failed; see body for error(s).' => array(
+      'Diff creation failed; see body for %s error(s).' => array(
         'Diff creation failed; see body for error.',
         'Diff creation failed; see body for errors.',
       ),
@@ -499,7 +499,7 @@
         'here:',
       ),
 
-      'PHP also loaded these configuration file(s):' => array(
+      'PHP also loaded these %s configuration file(s):' => array(
         'PHP also loaded this configuration file:',
         'PHP also loaded these configuration files:',
       ),
diff --git a/src/infrastructure/markup/interpreter/PhabricatorRemarkupCowsayBlockInterpreter.php b/src/infrastructure/markup/interpreter/PhabricatorRemarkupCowsayBlockInterpreter.php
--- a/src/infrastructure/markup/interpreter/PhabricatorRemarkupCowsayBlockInterpreter.php
+++ b/src/infrastructure/markup/interpreter/PhabricatorRemarkupCowsayBlockInterpreter.php
@@ -37,7 +37,9 @@
     if ($err) {
       return $this->markupError(
         pht(
-          'Execution of `cowsay` failed:', $stderr));
+          'Execution of `%s` failed: %s',
+          'cowsay',
+          $stderr));
     }