grammar - abbreviation for number neutral?

I don't know if this is the right place to ask this..

But when identifying pronouns, they are often given codes

1ms = 1st person masculine singular

and if a language, e.g. english and many others, don't specify gender in the first person, then C is (common?) gender..

1cs = (I guess) 1st person ("common?") singular

So "I" or "me" in English is given the pronoun abbreviation code 1cs

What about though, if the third letter in the abbreviation (the gender), is "common"? e.g. in English, in the second person "You" can be male or female, singular or plural. It's like 2cc (though i've not seen the abbreviation 2cc) What is the correct abbreviation to describe that neutral gender and neutral number?