Cannot add language to tag

Question

I have a PDF which was created in Adobe InDesign CS4. The document is mostly in English but has some Chinese and Spanish text. I am trying to mark the tags containg the Chinese or Spanish with the appropriate language.
In Acrobat Pro 9.1.2,
1. I select the Chinese text,
2. In the Tags panel I choose Find tag from selection.
3. I right-click the <span> tag which contains the Chinese text.
4. I choose properties.
Actual result: All fields on the Tags tab are grayed.
Expected result: All fields on the Tags tab, including the Language drop-down, are editable.
I have confirmed using the TouchUp Text tool that the file itself is editable. How to I make the tags editable?

Answer 1

When you save as PDF in FormsCentral, it Reader-enables the document, which prevents the type of changes you want to make. You can remove the usage rights by selecting "File > Save a Copy". You can then open the new PDF and make the changes you need. When you're done, you can re-enable in Acrobat 11 by selecting: File > Save as other > Reader Extended PDF > Enable More Tools