diff --git a/src/Executor/Executor.php b/src/Executor/Executor.php
index 463c7f2..b7fa041 100644
--- a/src/Executor/Executor.php
+++ b/src/Executor/Executor.php
@@ -430,7 +430,7 @@ class Executor
      * the passed in map of fields, and returns it at the end.
      *
      * CollectFields requires the "runtime type" of an object. For a field which
-     * returns and Interface or Union type, the "runtime type" will be the actual
+     * returns an Interface or Union type, the "runtime type" will be the actual
      * Object type returned by that field.
      *
      * @param ObjectType $runtimeType