There is no free version of Microsoft Office 2010 for Mac OS X 10.9.4. The latest version (Word 2011) is compatible with Mac OS X 10.5.8 or later. The free versions of Office packages are distributed through universities. In other case, you will have to buy the package or test it as a trial using the official website. Access the website and you will have the possibility to download a trial version for your Mac OS X.