The human language for each passage or phrase in the content must be determinable

Re-identify the appropriate language of the passage or phrase that does not match with the identified document language

In Acrobat Adobe Pro, using the Tags Pane:

For a block-level language change:

1. Open the Tags Pane
2. Right-click the tag that corresponds to the content with a language change
3. Select Properties
4. In the dialog, in the Tag tab, select the Language from the drop-down menu and then click close

For an inline language change:

1. Click the Selection Tool
2. Select the entire paragraph
3. Open the Options Menu in the Tags Pane
4. Select Create Tag from Selection
5. Select Paragraph from the drop-down menu and click OK
6. Open the Options Menu
7. Select New Tag
8. Select Span from the drop-down menu and click OK
9. Select the inline text with a language change
10. Right-click the Span tag
11. Select Create Tag from Selection
12. Drag and drop the Span tag to the correct place in the tag tree, since associating it with the Span tag pushed it out of the paragraph
13. Right-click the Span tag
14. Select Properties
15. In the Tag tab, select the Language from the drop-down menu and click Close

Note: Adobe Acrobat Pro is the most common tool for PDF remediations, but other tools and software are also available and can be used to remediate the PDF.