I come from China. In Korean, you can say "나는 중국에서 왔다" or "저는 중국 산동에서 왔습니다" to express "I come from China". As for how to say "hello" in Korean, there are several ways:
1. 안녕세요 (an nyeong ha se yo): This is the most common and formal way to say "hello" in Korean. It is pronounced with a flat tone, and the final "yo" has a rising tone.
2. 여러분 안녕세요 (yeo reo bun an nyeong ha se yo): This phrase is used to greet a group of people and can be translated as "hello everyone". It is pronounced in the same way as the previous phrase.
3. 안녕 (an nyeng): This is a more casual and informal way to say "hello". It is often used among friends or acquaintances. The pronunciation is the same as the previous phrases.
4. 안녕십니까 (an nyeong ha ship ni ka): This is a very formal and polite way to say "hello". It is commonly used in formal situations or when addressing someone of higher status. The pronunciation is the same as the previous phrases.
5. 안뇽 (an nyong): This is a shortened and informal version of "안녕". It is often used among close friends or peers. The pronunciation is the same as the previous phrases.
To summarize, in Korean, "hello" can be expressed as "안녕세요", "여러분 안녕세요", "안녕", "안녕십니까", or "안뇽". Each expression has its own level of formality and is used in different social contexts.