1 hour ago, ElsieD said:
Yes. It's Cantonese rice wine of cooking quality, rather than for drinking. The Chinese on the front label reads 廣東米酒 (guǎng dōng mǐ jiǔ) in Traditional Chinese characters as still used in Hong Kong, Taiwan and much of the Chinese diaspora. The reverse label repeats this, but in the simplified characters used in the Chinese mainland.
This refers to Guangdong, the Cantonese speaking mainland province opposite Hong Kong. Kwangtung is the Cantonese pronunciation for Guangdong (the Mandarin name). Mijiu is literally rice wine. It is not vinegar (unless it's been there a very long time).
The wine is mainly used in marinades and sauces with some Cantonese dishes.