Rewords for clarity.

Author: kenwith

articles/active-directory/app-provisioning/customize-application-attributes.md

@@ -66,12 +66,12 @@ Along with these four basic types, custom attribute-mappings support the concept
 
 ### Understanding attribute-mapping properties
 
-In the previous section, you were already introduced to the attribute-mapping type property.
-Along with this property, attribute-mappings also support the following attributes:
+In the previous section, you were introduced to the attribute-mapping type property.
+Along with this property, attribute-mappings also supports the attributes:
 
 - **Source attribute** - The user attribute from the source system (example: Azure Active Directory).
 - **Target attribute** – The user attribute in the target system (example: ServiceNow).
-- **Default value if null (optional)** - The value that is passed to the target system if the source attribute is null. This value is only provisioned when a user is created. The "default value when null" is not provisioned when updating an existing user. If for example, you provision all existing users in the target system with a particular Job Title (when it's null in the source system), you'll use the following [expression](../app-provisioning/functions-for-customizing-application-data.md): Switch(IsPresent([jobTitle]), "DefaultValue", "True", [jobTitle]). Make sure to replace the "Default Value" with the value to provision when null in the source system. 
+- **Default value if null (optional)** - The value that is passed to the target system if the source attribute is null. This value is only provisioned when a user is created. The "default value when null" is not provisioned when updating an existing user. For example, to add a default value for job title you would use the expression: `Switch(IsPresent([jobTitle]), "DefaultValue", "True", [jobTitle])`. To learn more about expressions, see [Reference for writing expressions for attribute mappings in Azure Active Directory](../app-provisioning/functions-for-customizing-application-data.md).
 - **Match objects using this attribute** – Whether this mapping should be used to uniquely identify users between the source and target systems. It's typically set on the userPrincipalName or mail attribute in Azure AD, which is typically mapped to a username field in a target application.
 - **Matching precedence** – Multiple matching attributes can be set. When there are multiple, they're evaluated in the order defined by this field. As soon as a match is found, no further matching attributes are evaluated. While you can set as many matching attributes as you would like, consider whether the attributes you're using as matching attributes are truly unique and need to be matching attributes. Generally customers have 1 or 2 matching attributes in their configuration. 
 - **Apply this mapping**