Based on this passage, please extract the names of the countries where TSMC has semiconductor fabrication (or "fab") facilities and separate them by commas.

Context: Apart from its main base of operations in Hsinchu in Northern Taiwan, where several of its fab facilities are located, it also has leading-edge fabs in Southern Taiwan and Central Taiwan, with other fabs located at its subsidiaries TSMC China in Shanghai, China, WaferTech in Washington state, United States, and SSMC in Singapore, and it has offices in China, Europe, India, Japan, North America, and South Korea.

Answer: Taiwan, China, United States, Singapore