what do they call it? = correct what's it called? = more polite What is correct? = the better choice for question #2 How is correct? = specificly asking if the word ¨how¨ is correct in the situation I hope this helps! Let me know if you have any other questions!

What- connotes clarity How- connotes the manner in which it was done

Both of the options are used for two different reasons but the correct one to use in your scenario would be the first one. "How do they call it?"- Is a question used to ask how something that you already know the name of is pronounced. Your second question also consists of two question with different meanings. "How is correct?"- This is a question used when you need someone to explain how something would be correct and the correct way to ask it would be "How is it correct?" "What is correct?"- Firstly, you would want to rephrase how you ask the question because "What is correct?" does not give depth and would leave the listener confused. Instead, I would recommend you use "Which one is correct?" which would mean that you were given several possible answers and you did not know which one is correct. The difference between the two question-sentences would be the you would usually ask someone "Which one is correct?" first and then follow up with "How is it correct?" so that they can give you an explanation as to why they think that specific answer is correct.