Assembly: Microsoft.Office.Interop.Word (in microsoft.office.interop.word.dll)
Use the Languages property to return the Languages collection.
Use Languages(index) to return a single Language object, where index can be the value of the Name property, the value of the NameLocal property, one of the WdLanguageID constants, or one of the Microsoft.Office.Core.MsoLanguageID constants.
The Count property returns the number of languages for which you can mark text (languages for which proofing tools are available). To check proofing, you must install the appropriate tools for each language you intend to check. You need both a .dll file and an .lex file for each of the following: the thesaurus, spelling checker, grammar checker, and hyphenation tools.
If you mark text as wdNoProofing, Word skips the marked text when running a spelling or grammar check. To mark text for a specified language or for no proofing, use the Set Language command (Tools menu, Language sub menu).