diff --git a/libempathy-gtk/empathy-account-widget.c b/libempathy-gtk/empathy-account-widget.c
index ab34763..679b515 100644
--- a/libempathy-gtk/empathy-account-widget.c
+++ b/libempathy-gtk/empathy-account-widget.c
@@ -2000,6 +2000,8 @@ add_enable_checkbox (EmpathyAccountWidget *self,
 
   gtk_widget_show (w);
 #else
+  /* translators: this is the label of a checkbox used to enable/disable IM
+   * accounts */
   priv->enabled_checkbox =
       gtk_check_button_new_with_mnemonic (_("_Enabled"));
 
diff --git a/libempathy/empathy-utils.c b/libempathy/empathy-utils.c
index 663c500..ae4209b 100644
--- a/libempathy/empathy-utils.c
+++ b/libempathy/empathy-utils.c
@@ -312,6 +312,7 @@ empathy_presence_get_default_message (TpConnectionPresenceType presence)
 	case TP_CONNECTION_PRESENCE_TYPE_OFFLINE:
 		return _("Offline");
 	case TP_CONNECTION_PRESENCE_TYPE_UNKNOWN:
+		/* translators: presence type is unknown */
 		return _("Unknown");
 	case TP_CONNECTION_PRESENCE_TYPE_UNSET:
 	case TP_CONNECTION_PRESENCE_TYPE_ERROR:
diff --git a/src/empathy-streamed-media-window.c b/src/empathy-streamed-media-window.c
index 390e2dd..bb6df68 100644
--- a/src/empathy-streamed-media-window.c
+++ b/src/empathy-streamed-media-window.c
@@ -1901,9 +1901,13 @@ reset_details_pane (EmpathyStreamedMediaWindow *self)
 {
   EmpathyStreamedMediaWindowPriv *priv = GET_PRIV (self);
 
+  /* translators: encoding video codec is unknown */
   gtk_label_set_text (GTK_LABEL (priv->vcodec_encoding_label), _("Unknown"));
+  /* translators: encoding audio codec is unknown */
   gtk_label_set_text (GTK_LABEL (priv->acodec_encoding_label), _("Unknown"));
+  /* translators: decoding video codec is unknown */
   gtk_label_set_text (GTK_LABEL (priv->vcodec_decoding_label), _("Unknown"));
+  /* translators: decoding audio codec is unknown */
   gtk_label_set_text (GTK_LABEL (priv->acodec_decoding_label), _("Unknown"));
 }
 
