Fix grammatical errors

Change-Id: I0bade79fc8c1ca528785732a2340d28f500830e5
diff --git a/core/api/src/main/java/org/onosproject/net/newresource/ResourceAdminService.java b/core/api/src/main/java/org/onosproject/net/newresource/ResourceAdminService.java
index e94ee45..cdcd407 100644
--- a/core/api/src/main/java/org/onosproject/net/newresource/ResourceAdminService.java
+++ b/core/api/src/main/java/org/onosproject/net/newresource/ResourceAdminService.java
@@ -26,7 +26,7 @@
 @Beta
 public interface ResourceAdminService {
     /**
-     * Register resources as the children of the parent resource path.
+     * Registers resources as the children of the parent resource path.
      *
      * @param parent parent resource path under which the resource are registered
      * @param children resources to be registered as the children of the parent
@@ -39,7 +39,7 @@
     }
 
     /**
-     * Register resources as the children of the parent resource path.
+     * Registers resources as the children of the parent resource path.
      *
      * @param parent parent resource path under which the resource are registered
      * @param children resources to be registered as the children of the parent
@@ -50,7 +50,7 @@
     <T> boolean registerResources(ResourcePath parent, List<T> children);
 
     /**
-     * Unregister resources as the children of the parent resource path.
+     * Unregisters resources as the children of the parent resource path.
      *
      * @param parent parent resource path under which the resource are unregistered
      * @param children resources to be unregistered as the children of the parent
@@ -63,7 +63,7 @@
     }
 
     /**
-     * Unregister resources as the children of the parent resource path.
+     * Unregisters resources as the children of the parent resource path.
      *
      * @param parent parent resource path under which the resource are unregistered
      * @param children resources to be unregistered as the children of the parent