You can set a document as read-only and still allow editing only for some selected parts.
To allow changes to selected parts
- Click Restrict Editing in the Review tab.
- In the Restrict Editing task pane, select the Allow only this type of editing in the document: Fill out a form check box.
- Click Yes, Start Enforcing Protection.
- In the Start Enforcing Protection dialog box, type password, and then click OK.
- If another user open this document without knowing the password, changes to selected parts are only allowed.