Koryo (also, Koryomar, Goryeomal, Koryŏmal, or Goremal) is an endangered variety of the Korean language from Uzbekistan, Russia, Kazakhstan, Ukraine, and Kyrgyzstan and spoken by the Koryosaram community. In this video, Olga also speaks Russian.

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"Koryomar, Goryeomal, or Koryŏmal (Korean: 고려말, Russian: Корё мар), otherwise known as Goremal (고레말) by speakers of the dialect, is a dialect of Korean spoken by the Koryosaram, ethnic Koreans in the countries of the former Soviet Union. It is descended from the Hamgyŏng dialect and multiple other varieties of Northeastern Korean.[1] Koryosaram is often reported as difficult to understand by speakers of standard Korean; this may be compounded by the fact that the majority of Koryosaram today use Russian and not Korean as their first language.[2] According to German Kim, Koryomar is not widely used in the media and is not taught in schools. Thus it can be classified as endangered.[3]"

"Russian (русский язык, tr. rússkiy yazýk) is an East Slavic language native to the Russians in Eastern Europe. It is an official language in Russia, Belarus, Kazakhstan, Kyrgyzstan, as well as being widely used throughout the Baltic states, the Caucasus and Central Asia. Russian belongs to the family of IndoEuropean languages, one of the four living members of the East Slavic languages alongside, and part of the larger BaltoSlavic branch. There is a high degree of mutual intelligibility between Russian, Belarusian and Ukrainian. Russian was the de facto language of the Soviet Union until its dissolution on 26 December 1991. Russian is used in official capacity or in public life in all the postSoviet nationstates. Large numbers of Russian speakers can also be found in other countries, such as Israel and Mongolia. Russian is the largest native language in Europe, and the most geographically widespread language in Eurasia. It is the most widely spoken of the Slavic languages, with over 258 million total speakers worldwide. Russian is the seventhmost spoken language in the world by number of native speakers and the eighthmost spoken language in the world by total number of speakers. The language is one of the six official languages of the United Nations. Russian is also the secondmost widespread language on the Internet, after English.Russian is written using the Cyrillic script; it distinguishes between consonant phonemes with palatal secondary articulation and those without, the socalled soft and hard sounds. Almost every consonant has a hard or a soft counterpart, and the distinction is a prominent feature of the language. Another important aspect is the reduction of unstressed vowels. Stress, which is unpredictable, is not normally indicated orthographically though an optional acute accent may be used to mark stress, such as to distinguish between homographic words, for example замо́к (zamók – a lock) and за́мок (zámok – a castle), or to indicate the proper pronunciation of uncommon words or names."