Language
In Taiwan, most people use two languages, Mainland Chinese, also known as Mandarin, and secondly Hokkien, English is also widely used here and is printed in Chinese on websites and direction boards. So prepare yourself basic English to communicate although Taiwanese people do not speak English as much as Singaporeans or Hong Kongers, you will definitely need it when you go to places like hotels, and shopping malls. The most basic shopping is at the airport. However, you should have to learn some Chinese sentences to protect yourself because not all Taiwanese know English and not everyone who knows English can speak it easily.
A little tip for those with poor foreign language communication skills, use body language as much as possible or simply download language translation apps to your smartphone that don't need wifi or 3G (in case you go to places where there is no wifi in Taiwan such as snacking places,..).