diff --git a/wp-admin/includes/ajax-actions.php b/wp-admin/includes/ajax-actions.php
index 6f38d2221c..531d8ad3f6 100644
--- a/wp-admin/includes/ajax-actions.php
+++ b/wp-admin/includes/ajax-actions.php
@@ -1272,7 +1272,7 @@ function wp_ajax_replyto_comment( $action ) {
 	if ( empty( $post->post_status ) ) {
 		wp_die( 1 );
 	} elseif ( in_array( $post->post_status, array( 'draft', 'pending', 'trash' ) ) ) {
-		wp_die( __( 'ERROR: you are replying to a comment on a draft post.' ) );
+		wp_die( __( 'ERROR: You are replying to a comment on a draft post.' ) );
 	}
 
 	$user = wp_get_current_user();
@@ -1302,7 +1302,7 @@ function wp_ajax_replyto_comment( $action ) {
 	}
 
 	if ( '' == $comment_content ) {
-		wp_die( __( 'ERROR: please type a comment.' ) );
+		wp_die( __( 'ERROR: Please type a comment.' ) );
 	}
 
 	$comment_parent = 0;
@@ -1404,7 +1404,7 @@ function wp_ajax_edit_comment() {
 	}
 
 	if ( '' == $_POST['content'] ) {
-		wp_die( __( 'ERROR: please type a comment.' ) );
+		wp_die( __( 'ERROR: Please type a comment.' ) );
 	}
 
 	if ( isset( $_POST['status'] ) ) {
diff --git a/wp-admin/options.php b/wp-admin/options.php
index 4f4264e92d..8a8d7b8f06 100644
--- a/wp-admin/options.php
+++ b/wp-admin/options.php
@@ -217,7 +217,7 @@ if ( 'update' == $action ) {
 	}
 
 	if ( ! isset( $whitelist_options[ $option_page ] ) ) {
-		wp_die( __( '<strong>ERROR</strong>: options page not found.' ) );
+		wp_die( __( '<strong>ERROR</strong>: Options page not found.' ) );
 	}
 
 	if ( 'options' == $option_page ) {
diff --git a/wp-includes/comment.php b/wp-includes/comment.php
index 63ad45bc8e..18ff53e3af 100644
--- a/wp-includes/comment.php
+++ b/wp-includes/comment.php
@@ -1224,19 +1224,19 @@ function wp_check_comment_data_max_lengths( $comment_data ) {
 	$max_lengths = wp_get_comment_fields_max_lengths();
 
 	if ( isset( $comment_data['comment_author'] ) && mb_strlen( $comment_data['comment_author'], '8bit' ) > $max_lengths['comment_author'] ) {
-		return new WP_Error( 'comment_author_column_length', __( '<strong>ERROR</strong>: your name is too long.' ), 200 );
+		return new WP_Error( 'comment_author_column_length', __( '<strong>ERROR</strong>: Your name is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_author_email'] ) && strlen( $comment_data['comment_author_email'] ) > $max_lengths['comment_author_email'] ) {
-		return new WP_Error( 'comment_author_email_column_length', __( '<strong>ERROR</strong>: your email address is too long.' ), 200 );
+		return new WP_Error( 'comment_author_email_column_length', __( '<strong>ERROR</strong>: Your email address is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_author_url'] ) && strlen( $comment_data['comment_author_url'] ) > $max_lengths['comment_author_url'] ) {
-		return new WP_Error( 'comment_author_url_column_length', __( '<strong>ERROR</strong>: your url is too long.' ), 200 );
+		return new WP_Error( 'comment_author_url_column_length', __( '<strong>ERROR</strong>: Your url is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_content'] ) && mb_strlen( $comment_data['comment_content'], '8bit' ) > $max_lengths['comment_content'] ) {
-		return new WP_Error( 'comment_content_column_length', __( '<strong>ERROR</strong>: your comment is too long.' ), 200 );
+		return new WP_Error( 'comment_content_column_length', __( '<strong>ERROR</strong>: Your comment is too long.' ), 200 );
 	}
 
 	return true;
@@ -3352,9 +3352,9 @@ function wp_handle_comment_submission( $comment_data ) {
 
 	if ( get_option( 'require_name_email' ) && ! $user->exists() ) {
 		if ( '' == $comment_author_email || '' == $comment_author ) {
-			return new WP_Error( 'require_name_email', __( '<strong>ERROR</strong>: please fill the required fields (name, email).' ), 200 );
+			return new WP_Error( 'require_name_email', __( '<strong>ERROR</strong>: Please fill the required fields (name, email).' ), 200 );
 		} elseif ( ! is_email( $comment_author_email ) ) {
-			return new WP_Error( 'require_valid_email', __( '<strong>ERROR</strong>: please enter a valid email address.' ), 200 );
+			return new WP_Error( 'require_valid_email', __( '<strong>ERROR</strong>: Please enter a valid email address.' ), 200 );
 		}
 	}
 
@@ -3379,7 +3379,7 @@ function wp_handle_comment_submission( $comment_data ) {
 	 */
 	$allow_empty_comment = apply_filters( 'allow_empty_comment', false, $commentdata );
 	if ( '' === $comment_content && ! $allow_empty_comment ) {
-		return new WP_Error( 'require_valid_comment', __( '<strong>ERROR</strong>: please type a comment.' ), 200 );
+		return new WP_Error( 'require_valid_comment', __( '<strong>ERROR</strong>: Please type a comment.' ), 200 );
 	}
 
 	$check_max_lengths = wp_check_comment_data_max_lengths( $commentdata );
diff --git a/wp-includes/ms-deprecated.php b/wp-includes/ms-deprecated.php
index 80b7f9faef..45141105da 100644
--- a/wp-includes/ms-deprecated.php
+++ b/wp-includes/ms-deprecated.php
@@ -410,7 +410,7 @@ function create_empty_blog( $domain, $path, $weblog_title, $site_id = 1 ) {
 	 */
 
 	if ( ! $blog_id = insert_blog($domain, $path, $site_id) )
-		return __( '<strong>ERROR</strong>: problem creating site entry.' );
+		return __( '<strong>ERROR</strong>: Problem creating site entry.' );
 
 	switch_to_blog($blog_id);
 	install_blog($blog_id);
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 65513e190d..ae275ba027 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4-alpha-47153';
+$wp_version = '5.4-alpha-47154';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.