The 'Languages' report in Google Analytics allows you to see which languages your audience's systems are set to, therefore giving you the opportunity to optimise content for them. Although the obvious benefits are for multi-national corporations or organisations dealing with multiple ethnic groups within a country - such as councils or charities - this report is also important to organisations considering foreign expansion. The languages report can help you develop website content to support entrance into foreign markets.
The Languages Report shows the relative importance of different language groups in terms of their quantity and quality, thereby informing any decisions relating to providing alternate language content on your website.
The language group zh-cn (People's Republic Chinese) represents a large portion of your website's audience yet the bounce rate is quite low. This could suggest that your audience is multi-lingual and your website may not need to accommodate them. However, if you were receiving high traffic from zh-cn and the bounce rate was high, you would have to look providing a translation for them, as they were clearly showing interest in your product offering, but were having difficulties processing your information.
The 'Goal Conversion' tab on the report also provides important information pertaining to the relevant importance of each language group to achieving the conversion goals your have set in Google Analytics. Again, poor performing language groups may need language specific content to improve conversions.
A full list of language codes and their translations is provided on our Google Analytics Help Centre