Adobe Reader comes equipped with a multilingual interface that allows users to adjust your language settings to any one of the varieties of global dialects, including English, Spanish, and Mandarin. All that's required is a quick tweak to your settings.
Open Adobe Reader, and click Edit > Preferences > International.
Next to Application Language, select Choose at Startup:
Click OK to apply, and then restart Adobe Reader.
Upon startup, you should be greeted by a small window prompting you to select the language of your choice:
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