Improve wording

docs/sources/features/datasources/cloudwatch.md

@@ -45,9 +45,9 @@ Checkout AWS docs on [IAM Roles](http://docs.aws.amazon.com/AWSEC2/latest/UserGu
 
 ## IAM Policies
 
-Grafana needs permissions granted via IAM to be able to read from CloudWatch
-and EC2. Attach these permissions to IAM roles to utilized Grafana's build-in
-role support.
+Grafana needs permissions granted via IAM to be able to read CloudWatch metrics
+and EC2 tags/instances. You can attach these permissions to IAM roles and
+utilize Grafana's built-in support for assuming roles.
 
 Here is a minimal policy example: