diff --git a/src/calibre/ebooks/conversion/plugins/pdb_output.py b/src/calibre/ebooks/conversion/plugins/pdb_output.py
index ec03e9706c..b4c67f1139 100644
--- a/src/calibre/ebooks/conversion/plugins/pdb_output.py
+++ b/src/calibre/ebooks/conversion/plugins/pdb_output.py
@@ -24,7 +24,7 @@ class PDBOutput(OutputFormatPlugin):
         OptionRecommendation(name='format', recommended_value='doc',
             level=OptionRecommendation.LOW,
             short_switch='f', choices=list(ALL_FORMAT_WRITERS),
-            help=(_('Format to use inside the pdb container. Choices are:') + ' %s' % sorted(ALL_FORMAT_WRITERS))),
+            help=(_('Format to use inside the PDB container. Choices are:') + ' %s' % sorted(ALL_FORMAT_WRITERS))),
         OptionRecommendation(name='pdb_output_encoding', recommended_value='cp1252',
             level=OptionRecommendation.LOW,
             help=_('Specify the character encoding of the output document. '
diff --git a/src/calibre/gui2/dialogs/metadata_bulk.py b/src/calibre/gui2/dialogs/metadata_bulk.py
index e58755613a..d9e7532eff 100644
--- a/src/calibre/gui2/dialogs/metadata_bulk.py
+++ b/src/calibre/gui2/dialogs/metadata_bulk.py
@@ -681,7 +681,7 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
                  'search text. The text is replaced by the specified replacement '
                  'text everywhere it is found in the specified field. After '
                  'replacement is finished, the text can be changed to '
-                 'upper-case, lower-case, or title-case. If the case-sensitive '
+                 'upper-case, lower-case, or title-case. If the Case-sensitive '
                  'check box is checked, the search text must match exactly. If '
                  'it is unchecked, the search text will match both upper- and '
                  'lower-case letters'
diff --git a/src/calibre/gui2/tag_browser/ui.py b/src/calibre/gui2/tag_browser/ui.py
index 991482dc35..5cb3f0264f 100644
--- a/src/calibre/gui2/tag_browser/ui.py
+++ b/src/calibre/gui2/tag_browser/ui.py
@@ -609,7 +609,7 @@ class TagBrowserWidget(QFrame):  # {{{
 
         mt = l.m.addAction(_('Manage authors, tags, etc.'))
         mt.setToolTip(_('All of these category_managers are available by right-clicking '
-                       'on items in the tag browser above'))
+                       'on items in the Tag browser above'))
         mt.m = l.manage_menu = QMenu(l.m)
         mt.setMenu(mt.m)