diff --git a/src/calibre/devices/kobo/kobotouch_config.py b/src/calibre/devices/kobo/kobotouch_config.py
index cb0fb4bcdb..a65eb5c815 100644
--- a/src/calibre/devices/kobo/kobotouch_config.py
+++ b/src/calibre/devices/kobo/kobotouch_config.py
@@ -586,7 +586,7 @@ class MetadataGroupBox(DeviceOptionsGroupBox):
         self.update_core_metadata_checkbox = create_checkbox(
                              _("Update metadata on Book Details pages"),
                              _('This will update the metadata in the device database when the device is connected. '
-                               'The metadata updated is displayed on the device in the library and the book details page. '
+                               'The metadata updated is displayed on the device in the library and the Book details page. '
                                'This is the title, authors, comments/synopsis, series name and number, publisher and published Date, ISBN and language. '
                                'If a metadata plugboard exists for the device and book format, this will be used to set the metadata.'
                                ),
diff --git a/src/calibre/gui2/actions/show_book_details.py b/src/calibre/gui2/actions/show_book_details.py
index 7469bc5572..4395b4e9ac 100644
--- a/src/calibre/gui2/actions/show_book_details.py
+++ b/src/calibre/gui2/actions/show_book_details.py
@@ -31,7 +31,7 @@ class ShowBookDetailsAction(InterfaceAction):
             icon='drm-locked.png', shortcut=None)
         l.triggered.connect(self.open_locked_window)
         l = self.create_menu_action(m,
-            'close_all_details', _('Close all book details windows'), icon='close.png', shortcut=None)
+            'close_all_details', _('Close all Book details windows'), icon='close.png', shortcut=None)
         l.triggered.connect(self.close_all_windows)
         self.qaction.triggered.connect(self.show_book_info)
 
diff --git a/src/calibre/gui2/preferences/create_custom_column.py b/src/calibre/gui2/preferences/create_custom_column.py
index 07a21141d1..01b22b2377 100644
--- a/src/calibre/gui2/preferences/create_custom_column.py
+++ b/src/calibre/gui2/preferences/create_custom_column.py
@@ -457,9 +457,9 @@ class CreateCustomColumn(QDialog):
         l.addStretch()
         add_row(None, l)
         l = QHBoxLayout()
-        self.composite_in_comments_box = cmc = QCheckBox(_("Show with comments in book details"))
+        self.composite_in_comments_box = cmc = QCheckBox(_("Show with comments in Book details"))
         cmc.setToolTip('<p>' + _('If you check this box then the column contents '
-                                 'will show in the Comments section in book details. '
+                                 'will show in the Comments section in Book details. '
                                  'You can indicate whether not to have a header or '
                                  'to put a header above the column. If you want a '
                                  "header beside the data, don't check this box. "