Figure 1: qTranslate plugin
Although WordPress is multilingual by incorporating GNU's Gettext, when trying to achieve multilingualism on a single site, it encounters various difficult problems. There was a request for multilingualization in a certain development project, so I was researching various language plug-ins and found the "qTranslate" plug-in.
This plugin is an excellent plugin that allows you to manage the language of the entire site and the language management of each post (per content) all at once.

The introduction to being able to switch between multiple languages specified by the plugin in the menu of the admin panel (see Figure 2) is the beginning, and you can also switch languages from the front-end side of the site (although you need to create a separate UI for switching...). You can choose from a variety of switching methods, such as automating it according to your browser's language settings, manually switching visitors, or temporarily switching based on URL parameters.
And the ultimate feature is that you can post content in different languages at the same time for each individual post.
The biggest barrier to multilingual content on sites is that even if shared content such as site menus, footers, and buttons can be translated into other languages as language files, posts and other content must be managed separately. For example, posts uploaded in Japanese and posted in English are separate content, and a separate mechanism was needed to manage them as the same content. The UI of the post was also a bottleneck because it could not write articles in multiple languages at the same time, which made it difficult for the maintainability and convenience of the site, but this plugin solves these problems at once.
So, I tried to post this article in both Japanese and English. If you want to see the English version, please click this link.
Figure 3: Plugin Settings Screen
The current version of the "qTranslate" plugin is 2.5.34 on June 19, 2013, and the included Japanese translation file is outdated, so some parts are not translated, so I tried to translate it according to the latest version.
※ The latest translation will be reflected by placing (overwriting) the .mo file downloaded below in the lang folder of the qTranslate plugin.
qTranslate Plugin Japanese File
- MO format: qtranslate-ja.mo (27KB)
Confirmation of action: WordPress 3.5.1 / qTranslate 2.5.34