N4 — outside your level filter
Is said whole, with nothing composed onto it and takes no だ/です, so there are no forms to conjugate.
敬具
keiguYours sincerely (formal letter closing)N4expression
Example sentences2
まずはご報告まで。敬具
mazu wa go houkoku made. keigu
Just a quick note to let you know. Yours sincerely. formal
今後ともよろしくお願い申し上げます。敬具
kongo tomo yoroshiku onegai moushiagemasu. keigu
I look forward to your continued support. Yours sincerely. formal