Chinese writing uses characters, which represent entire words or concepts, not individual letters.
If you want to represent the sound "m" in Chinese, you would need to use a character that incorporates that sound, depending on the context of the word you are trying to write.
For example, the character "妈" (mā) is pronounced with the initial sound "m" and means "mother." However, the character itself doesn't represent the letter "m" directly.
To write "m" in Chinese, you would need to provide more information about the word or context you are trying to represent.