This attribute has a defined list of values, which include definitions that represent instructions for supplying content to translation services. This attribute should only be used if some sort of pre-processing is necessary to support translation of the content.
"property-name" — adds a property to a microdata item. The name of the property can be a word or URL, and the value is the ‘content’ of the element with this attribute.
The lang attribute (in no namespace) specifies the primary language for the element's contents and for any of the element's attributes that contain text. Its value must be a valid BCP 47 language tag.