diff --git a/core/core.api.php b/core/core.api.php
index 65a73d2e865d8401bec77447756d1cc560d4132e..6f539ccbd8ccb28b5a88c17106a7e1ccdf9da5f7 100644
--- a/core/core.api.php
+++ b/core/core.api.php
@@ -2021,7 +2021,7 @@ function hook_queue_info_alter(&$queues) {
 /**
  * Alter an email message created with MailManagerInterface->mail().
  *
- * hook_mail_alter() allows modification of email messages created and sent
+ * Hook hook_mail_alter() allows modification of email messages created and sent
  * with MailManagerInterface->mail(). Usage examples include adding and/or
  * changing message text, message fields, and message headers.
  *
diff --git a/core/includes/common.inc b/core/includes/common.inc
index 58ede5565c42c780ff7a24c93e7cf3cbbb2c8715..49cf6e104a72aafac9435f9aaf721716d9ab9634 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -408,8 +408,8 @@ function drupal_set_time_limit($time_limit) {
 /**
  * Returns the base URL path (i.e., directory) of the Drupal installation.
  *
- * base_path() adds a "/" to the beginning and end of the returned path if the
- * path is not empty. At the very least, this will return "/".
+ * Function base_path() adds a "/" to the beginning and end of the returned path
+ * if the path is not empty. At the very least, this will return "/".
  *
  * Examples:
  * - http://example.com returns "/" because the path is empty.
diff --git a/core/lib/Drupal/Component/Datetime/DateTimePlus.php b/core/lib/Drupal/Component/Datetime/DateTimePlus.php
index cb23cba578671fe9c0b5dc5b5ce0531e50f5ec70..6c4a3b1491cf71896fd8e78ed77da638e74dbc95 100644
--- a/core/lib/Drupal/Component/Datetime/DateTimePlus.php
+++ b/core/lib/Drupal/Component/Datetime/DateTimePlus.php
@@ -46,7 +46,7 @@ class DateTimePlus {
   /**
    * A RFC7231 Compliant date.
    *
-   * http://tools.ietf.org/html/rfc7231#section-7.1.1.1
+   * @see http://tools.ietf.org/html/rfc7231#section-7.1.1.1
    *
    * Example: Sun, 06 Nov 1994 08:49:37 GMT
    */
diff --git a/core/lib/Drupal/Component/Utility/Html.php b/core/lib/Drupal/Component/Utility/Html.php
index 6c162ed09531fbe312ffd9a2d392231aa96f569b..b3893d68457123d6f920a66ac55705a85f634aa3 100644
--- a/core/lib/Drupal/Component/Utility/Html.php
+++ b/core/lib/Drupal/Component/Utility/Html.php
@@ -79,9 +79,10 @@ public static function getClass($class) {
   /**
    * Prepares a string for use as a CSS identifier (element, class, or ID name).
    *
-   * http://www.w3.org/TR/CSS21/syndata.html#characters shows the syntax for
-   * valid CSS identifiers (including element names, classes, and IDs in
-   * selectors.)
+   * Link below shows the syntax for valid CSS identifiers (including element
+   * names, classes, and IDs in selectors).
+   *
+   * @see http://www.w3.org/TR/CSS21/syndata.html#characters
    *
    * @param string $identifier
    *   The identifier to clean.
diff --git a/core/lib/Drupal/Component/Utility/UrlHelper.php b/core/lib/Drupal/Component/Utility/UrlHelper.php
index 372803590d331436291d563271830036a1cf27f7..1d133c9d6b1508a2d183b3858d0af547f0c71c15 100644
--- a/core/lib/Drupal/Component/Utility/UrlHelper.php
+++ b/core/lib/Drupal/Component/Utility/UrlHelper.php
@@ -19,7 +19,7 @@ class UrlHelper {
   /**
    * Parses an array into a valid, rawurlencoded query string.
    *
-   * rawurlencode() is RFC3986 compliant, and as a consequence RFC3987
+   * Function rawurlencode() is RFC3986 compliant, and as a consequence RFC3987
    * compliant. The latter defines the required format of "URLs" in HTML5.
    * urlencode() is almost the same as rawurlencode(), except that it encodes
    * spaces as "+" instead of "%20". This makes its result non compliant to
diff --git a/core/lib/Drupal/Core/Access/AccessResult.php b/core/lib/Drupal/Core/Access/AccessResult.php
index b0590d0a11be6233e2611f12fdd769700ea8615e..3abbf331015bf4f4a03d8d5b6f8bfe0efd506481 100644
--- a/core/lib/Drupal/Core/Access/AccessResult.php
+++ b/core/lib/Drupal/Core/Access/AccessResult.php
@@ -426,9 +426,9 @@ public function andIf(AccessResultInterface $other) {
   /**
    * Inherits the cacheability of the other access result, if any.
    *
-   * inheritCacheability() differs from addCacheableDependency() in how it
-   * handles max-age, because it is designed to inherit the cacheability of the
-   * second operand in the andIf() and orIf() operations. There, the situation
+   * This method differs from addCacheableDependency() in how it handles
+   * max-age, because it is designed to inherit the cacheability of the second
+   * operand in the andIf() and orIf() operations. There, the situation
    * "allowed, max-age=0 OR allowed, max-age=1000" needs to yield max-age 1000
    * as the end result.
    *
diff --git a/core/lib/Drupal/Core/Asset/LibraryDiscovery.php b/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
index a49ea975c39c93d4e7491013ea324a9c54b90ada..39c3e2b1a31dd885b055b3467952ec1b31904cef 100644
--- a/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
+++ b/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
@@ -19,7 +19,7 @@ class LibraryDiscovery implements LibraryDiscoveryInterface {
   /**
    * The final library definitions, statically cached.
    *
-   * hook_library_info_alter() and hook_js_settings_alter() allows modules
+   * Hooks hook_library_info_alter() and hook_js_settings_alter() allow modules
    * and themes to dynamically alter a library definition (once per request).
    *
    * @var array
diff --git a/core/lib/Drupal/Core/DependencyInjection/Compiler/TwigExtensionPass.php b/core/lib/Drupal/Core/DependencyInjection/Compiler/TwigExtensionPass.php
index 73ee17b68aa9255b8652a0fb2e7ff7e595d941bb..0f2bdb038aa1143f58fe07a09492a2fbb4568aa5 100644
--- a/core/lib/Drupal/Core/DependencyInjection/Compiler/TwigExtensionPass.php
+++ b/core/lib/Drupal/Core/DependencyInjection/Compiler/TwigExtensionPass.php
@@ -9,8 +9,8 @@
 /**
  * Adds the twig_extension_hash parameter to the container.
  *
- * twig_extension_hash is a hash of all extension mtimes for Twig template
- * invalidation.
+ * Parameter twig_extension_hash is a hash of all extension mtimes for Twig
+ * template invalidation.
  */
 class TwigExtensionPass implements CompilerPassInterface {
 
diff --git a/core/lib/Drupal/Core/Extension/module.api.php b/core/lib/Drupal/Core/Extension/module.api.php
index 32b7d7fdf4acbfbf3a213768031d72dc8e22f02d..76c49b5b72e4ed6ce0a7d5858802605538de6367 100644
--- a/core/lib/Drupal/Core/Extension/module.api.php
+++ b/core/lib/Drupal/Core/Extension/module.api.php
@@ -479,7 +479,7 @@ function hook_install_tasks_alter(&$tasks, $install_state) {
 /**
  * Perform a single update between minor versions.
  *
- * hook_update_N() can only be used to update between minor versions of a
+ * Hook hook_update_N() can only be used to update between minor versions of a
  * module. To upgrade between major versions of Drupal (for example, between
  * Drupal 7 and 8), use the @link migrate Migrate API @endlink instead.
  *
diff --git a/core/lib/Drupal/Core/Form/FormState.php b/core/lib/Drupal/Core/Form/FormState.php
index 5585a76234e60796cea0452b29d418c43f54a252..595079f4ad7a475f011e9328566e448454ff128b 100644
--- a/core/lib/Drupal/Core/Form/FormState.php
+++ b/core/lib/Drupal/Core/Form/FormState.php
@@ -609,13 +609,13 @@ public function setRequestMethod($method) {
   /**
    * Checks whether the request method is a "safe" HTTP method.
    *
-   * http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.1 defines
-   * GET and HEAD as "safe" methods, meaning they SHOULD NOT have side-effects,
-   * such as persisting $form_state changes.
+   * Link below defines GET and HEAD as "safe" methods, meaning they SHOULD NOT
+   * have side-effects, such as persisting $form_state changes.
    *
    * @return bool
    *
    * @see \Symfony\Component\HttpFoundation\Request::isMethodSafe()
+   * @see http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.1
    */
   protected function isRequestMethodSafe() {
     return in_array($this->requestMethod, ['GET', 'HEAD']);
diff --git a/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php b/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
index 7b171f8202fe85d32a6e36f49b70c243d7124481..b1e8fb0e7681e06dddbf22ef4f46996da5a1b05d 100644
--- a/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
+++ b/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
@@ -384,8 +384,8 @@ protected function processHtmlHead(array $html_head) {
   /**
    * Transform a html_head_link array into html_head and http_header arrays.
    *
-   * html_head_link is a special case of html_head which can be present as
-   * a link item in the HTML head section, and also as a Link: HTTP header,
+   * Variable html_head_link is a special case of html_head which can be present
+   * as a link item in the HTML head section, and also as a Link: HTTP header,
    * depending on options in the render array. Processing it can add to both the
    * html_head and http_header sections.
    *
diff --git a/core/lib/Drupal/Core/Routing/NullGenerator.php b/core/lib/Drupal/Core/Routing/NullGenerator.php
index 74db5c969225c432c331c408151c3bee945c444e..630e81ffe26bfd2703fcb5e1e50c2c980d30d5e8 100644
--- a/core/lib/Drupal/Core/Routing/NullGenerator.php
+++ b/core/lib/Drupal/Core/Routing/NullGenerator.php
@@ -27,8 +27,8 @@ public function __construct(RequestStack $request_stack) {
   /**
    * {@inheritdoc}
    *
-   * generate(), generateFromRoute(), and getPathFromRoute() all call this
-   * protected method.
+   * Methods generate(), generateFromRoute() and getPathFromRoute() all call
+   * this protected method.
    */
   protected function getRoute($name) {
     if ($name === '<front>') {
diff --git a/core/lib/Drupal/Core/Update/UpdateKernel.php b/core/lib/Drupal/Core/Update/UpdateKernel.php
index 31b86c835aa20aaef2932e52e9a345a723675974..24a5755e3061696b1c0c7467958a3ac41deb5bb7 100644
--- a/core/lib/Drupal/Core/Update/UpdateKernel.php
+++ b/core/lib/Drupal/Core/Update/UpdateKernel.php
@@ -115,7 +115,7 @@ protected function handleRaw(Request $request) {
   /**
    * Boots up the session.
    *
-   * bootSession() + shutdownSession() basically simulates what
+   * This method + shutdownSession() basically simulates what
    * \Drupal\Core\StackMiddleware\Session does.
    *
    * @param \Symfony\Component\HttpFoundation\Request $request
diff --git a/core/modules/field/tests/src/Kernel/TranslationTest.php b/core/modules/field/tests/src/Kernel/TranslationTest.php
index 17620e8c5dae081f1bfe17cafc60d83dcbe1b4d9..5d03f6917144af0c74093396ef5611161988332f 100644
--- a/core/modules/field/tests/src/Kernel/TranslationTest.php
+++ b/core/modules/field/tests/src/Kernel/TranslationTest.php
@@ -18,7 +18,7 @@ class TranslationTest extends FieldKernelTestBase {
   /**
    * Modules to enable.
    *
-   * node is required because the tests alter the node entity type.
+   * The node module is required because the tests alter the node entity type.
    *
    * @var array
    */
diff --git a/core/modules/filter/tests/src/Kernel/FilterAPITest.php b/core/modules/filter/tests/src/Kernel/FilterAPITest.php
index ad26dc4e375cf4fc5c06fae1706ab4620e5cd849..a26005db192b26ce23028b8dee6147f582da102f 100644
--- a/core/modules/filter/tests/src/Kernel/FilterAPITest.php
+++ b/core/modules/filter/tests/src/Kernel/FilterAPITest.php
@@ -246,9 +246,9 @@ public function testFilterFormatAPI() {
   /**
    * Tests the 'processed_text' element.
    *
-   * check_markup() is a wrapper for the 'processed_text' element, for use in
-   * simple scenarios; the 'processed_text' element has more advanced features:
-   * it lets filters attach assets, associate cache tags and define
+   * Function check_markup() is a wrapper for the 'processed_text' element, for
+   * use in simple scenarios; the 'processed_text' element has more advanced
+   * features: it lets filters attach assets, associate cache tags and define
    * #lazy_builder callbacks.
    * This test focuses solely on those advanced features.
    */
diff --git a/core/modules/image/src/Tests/ImageFieldTestBase.php b/core/modules/image/src/Tests/ImageFieldTestBase.php
index 2e21739abd4092938646911f6ca69959d353f03d..a1611cb3522df5732de4031722cf2e846b6eac44 100644
--- a/core/modules/image/src/Tests/ImageFieldTestBase.php
+++ b/core/modules/image/src/Tests/ImageFieldTestBase.php
@@ -10,11 +10,12 @@
 /**
  * TODO: Test the following functions.
  *
- * image.effects.inc:
+ * In file:
+ * - image.effects.inc:
  *   image_style_generate()
  *   \Drupal\image\ImageStyleInterface::createDerivative()
  *
- * image.module:
+ * - image.module:
  *   image_style_options()
  *   \Drupal\image\ImageStyleInterface::flush()
  *   image_filter_keyword()
diff --git a/core/modules/image/tests/src/Functional/ImageDimensionsTest.php b/core/modules/image/tests/src/Functional/ImageDimensionsTest.php
index 46eef05d9b021982d60781444c12c35e783d310f..4a11bf956eb55af909b3e20062bc7a8b993ced5b 100644
--- a/core/modules/image/tests/src/Functional/ImageDimensionsTest.php
+++ b/core/modules/image/tests/src/Functional/ImageDimensionsTest.php
@@ -286,9 +286,9 @@ public function testImageDimensions() {
   /**
    * Render an image style element.
    *
-   * drupal_render() alters the passed $variables array by adding a new key
-   * '#printed' => TRUE. This prevents next call to re-render the element. We
-   * wrap drupal_render() in a helper protected method and pass each time a
+   * Function drupal_render() alters the passed $variables array by adding a new
+   * key '#printed' => TRUE. This prevents next call to re-render the element.
+   * We wrap drupal_render() in a helper protected method and pass each time a
    * fresh array so that $variables won't get altered and the element is
    * re-rendered each time.
    */
diff --git a/core/modules/image/tests/src/Functional/ImageFieldTestBase.php b/core/modules/image/tests/src/Functional/ImageFieldTestBase.php
index b6484a84e90d519b79c1e15340a04b73f5d12c49..ef79de850372101895e0068ef6f903ddf74ec08a 100644
--- a/core/modules/image/tests/src/Functional/ImageFieldTestBase.php
+++ b/core/modules/image/tests/src/Functional/ImageFieldTestBase.php
@@ -8,11 +8,12 @@
 /**
  * TODO: Test the following functions.
  *
- * image.effects.inc:
+ * In file:
+ * - image.effects.inc:
  *   image_style_generate()
  *   \Drupal\image\ImageStyleInterface::createDerivative()
  *
- * image.module:
+ * - image.module:
  *   image_style_options()
  *   \Drupal\image\ImageStyleInterface::flush()
  *   image_filter_keyword()
diff --git a/core/modules/rest/tests/src/Functional/EntityResource/Comment/CommentResourceTestBase.php b/core/modules/rest/tests/src/Functional/EntityResource/Comment/CommentResourceTestBase.php
index 4cbc4fce07aadb211fb7ed555fe8d085af56082a..52168967681c6ee0405136592ab25bc302d5e97c 100644
--- a/core/modules/rest/tests/src/Functional/EntityResource/Comment/CommentResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/EntityResource/Comment/CommentResourceTestBase.php
@@ -267,8 +267,8 @@ protected function getExpectedCacheContexts() {
   /**
    * Tests POSTing a comment without critical base fields.
    *
-   * testPost() is testing with the most minimal normalization possible: the one
-   * returned by ::getNormalizedPostEntity().
+   * Tests with the most minimal normalization possible: the one returned by
+   * ::getNormalizedPostEntity().
    *
    * But Comment entities have some very special edge cases:
    * - base fields that are not marked as required in
diff --git a/core/modules/search/tests/src/Functional/SearchTokenizerTest.php b/core/modules/search/tests/src/Functional/SearchTokenizerTest.php
index 7862ea644867730fbef9abccced0839e85a5b47f..2cc2c6e4a2f0fd537f9093dba81f4c6b762568aa 100644
--- a/core/modules/search/tests/src/Functional/SearchTokenizerTest.php
+++ b/core/modules/search/tests/src/Functional/SearchTokenizerTest.php
@@ -123,9 +123,9 @@ public function testNoTokenizer() {
   /**
    * Like PHP chr() function, but for unicode characters.
    *
-   * chr() only works for ASCII characters up to character 255. This function
-   * converts a number to the corresponding unicode character. Adapted from
-   * functions supplied in comments on several functions on php.net.
+   * Function chr() only works for ASCII characters up to character 255. This
+   * function converts a number to the corresponding unicode character. Adapted
+   * from functions supplied in comments on several functions on php.net.
    */
   public function code2utf($num) {
     if ($num < 128) {
diff --git a/core/modules/system/src/Tests/Theme/ThemeSuggestionsAlterTest.php b/core/modules/system/src/Tests/Theme/ThemeSuggestionsAlterTest.php
index 2277adb342b4baae8062aa5d102af449a85b8727..7337dae4021171964f5ac2ea9999e11ebbff2561 100644
--- a/core/modules/system/src/Tests/Theme/ThemeSuggestionsAlterTest.php
+++ b/core/modules/system/src/Tests/Theme/ThemeSuggestionsAlterTest.php
@@ -154,7 +154,7 @@ public function testSuggestionsAlterInclude() {
   /**
    * Tests execution order of theme suggestion alter hooks.
    *
-   * hook_theme_suggestions_alter() should fire before
+   * Hook hook_theme_suggestions_alter() should fire before
    * hook_theme_suggestions_HOOK_alter() within an extension (module or theme).
    */
   public function testExecutionOrder() {
diff --git a/core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.module b/core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.module
index ee280a3b044d9328b08b28815f4d318ee4e3d122..31373cb59d4a3d121b338a4d2d427cd1eabb14e3 100644
--- a/core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.module
+++ b/core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.module
@@ -8,8 +8,8 @@
 /**
  * Implements hook_cron().
  *
- * common_test_cron() throws an exception, but the execution should reach this
- * function as well.
+ * Function common_test_cron() throws an exception, but the execution should
+ * reach this function as well.
  *
  * @see common_test_cron()
  */
diff --git a/core/phpcs.xml.dist b/core/phpcs.xml.dist
index 30c8688ef69d80a0e2cf53fa14229da1212280ef..55b8d59f83820b87631ef847e98c5feed614ffc2 100644
--- a/core/phpcs.xml.dist
+++ b/core/phpcs.xml.dist
@@ -42,8 +42,7 @@
   <rule ref="Drupal.Commenting.DocComment">
     <!-- Sniff for these errors: SpacingAfterTagGroup, WrongEnd, SpacingBetween,
       ContentAfterOpen, SpacingBeforeShort, TagValueIndent, ShortStartSpace,
-      SpacingAfter -->
-    <exclude name="Drupal.Commenting.DocComment.LongNotCapital"/>
+      SpacingAfter, LongNotCapital -->
     <!-- ParamNotFirst still not decided for PHPUnit-based tests.
       @see https://www.drupal.org/node/2253915 -->
     <exclude name="Drupal.Commenting.DocComment.ParamNotFirst"/>
diff --git a/core/tests/Drupal/KernelTests/AssertContentTrait.php b/core/tests/Drupal/KernelTests/AssertContentTrait.php
index 1558320d7f3493b25322cad35eb646c4ebec83e0..e075ffe857f89bf911a1d935f3ce8af6f6fc91a8 100644
--- a/core/tests/Drupal/KernelTests/AssertContentTrait.php
+++ b/core/tests/Drupal/KernelTests/AssertContentTrait.php
@@ -31,7 +31,7 @@ trait AssertContentTrait {
   /**
    * The drupalSettings value from the current raw $content.
    *
-   * drupalSettings refers to the drupalSettings JavaScript variable.
+   * Variable drupalSettings refers to the drupalSettings JavaScript variable.
    *
    * @var array
    */
@@ -99,7 +99,7 @@ protected function removeWhiteSpace() {
   /**
    * Gets the value of drupalSettings for the currently-loaded page.
    *
-   * drupalSettings refers to the drupalSettings JavaScript variable.
+   * Variable drupalSettings refers to the drupalSettings JavaScript variable.
    */
   protected function getDrupalSettings() {
     return $this->drupalSettings;
@@ -108,7 +108,7 @@ protected function getDrupalSettings() {
   /**
    * Sets the value of drupalSettings for the currently-loaded page.
    *
-   * drupalSettings refers to the drupalSettings JavaScript variable.
+   * Variable drupalSettings refers to the drupalSettings JavaScript variable.
    */
   protected function setDrupalSettings($settings) {
     $this->drupalSettings = $settings;
diff --git a/core/tests/Drupal/KernelTests/Core/Asset/AttachedAssetsTest.php b/core/tests/Drupal/KernelTests/Core/Asset/AttachedAssetsTest.php
index 14288fee8e00d35d81584ef11728283d03380b2d..2a9ea0b3476afdda71cd3cfbf5de0b8bd2e15ccb 100644
--- a/core/tests/Drupal/KernelTests/Core/Asset/AttachedAssetsTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Asset/AttachedAssetsTest.php
@@ -9,7 +9,7 @@
 /**
  * Tests #attached assets: attached asset libraries and JavaScript settings.
  *
- * i.e. tests:
+ * I.e. tests:
  *
  * @code
  * $build['#attached']['library'] = …
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
index 9b279a5e1df8c981d20d30f5b8ea55949b70f266..16fd8c5797e97e1a328a4d51ef36392fe9f38721 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
@@ -57,7 +57,7 @@ protected function setUp() {
   /**
    * Checks the order of CRUD hook execution messages.
    *
-   * entity_crud_hook_test.module implements all core entity CRUD hooks and
+   * Module entity_crud_hook_test implements all core entity CRUD hooks and
    * stores a message for each in $GLOBALS['entity_crud_hook_test'].
    *
    * @param $messages
diff --git a/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php b/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
index acb7346db0d3b9f1792e417fce7f709a47c49a42..adcb3345579fa502208f5e189c5e603c00b6fe96 100644
--- a/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
+++ b/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
@@ -65,8 +65,8 @@ abstract protected function getPluginId();
   /**
    * Returns the module name and the module directory for the plugin.
    *
-   * drupal_get_path() cannot be used here, because it is not available in
-   * Drupal PHPUnit tests.
+   * Function drupal_get_path() cannot be used here, because it is not available
+   * in Drupal PHPUnit tests.
    *
    * @return array
    *   A one-dimensional array containing the following strings:
diff --git a/core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php b/core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php
index 0d38afd10612bf014ecabe896e988026a105ee83..36137b4a00d000ffd8d2d443b244a2bca5cb8346 100644
--- a/core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php
+++ b/core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php
@@ -35,7 +35,7 @@ protected function setUp() {
   /**
    * Provides the two classes of placeholders: cacheable and uncacheable.
    *
-   * i.e. with or without #cache[keys].
+   * I.e. with or without #cache[keys].
    *
    * Also, different types:
    * - A) automatically generated placeholder