Remember the users language on the splash page and redirect them to the remembered language of the user.

jorenvh

Using the wpml plugin for multi language WordPress sites you can choose to have a custom file or WordPress page 
to be used for the root url, like a splash page for the main language selection. (Ex. http://www.yoursite.com). 
The thing here is that every time a user enters your site using the root url they will see this page again. 
You may only want to show this page when the user is new.
This is where this plugin comes in handy, we save the prefered language in a cookie and as long as this cookie is there 
the user can enter the site using the root url, but he will always redirect to his language of choice from his previous visit.

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