dear sir，
i take the liberty to write you in the hope that you might need someone to fill in for you. i feel that i am qualified as an administrator.
i am currently a student at college, i have over a month more to complete before i graduate. my major is business administration.
i have excellent grades in all my subjects. if you wish to look at these information it will be sent to you later.
i have worked at a trading company as a secretary, but i hope to seek more responsible employment.
i am 25 years old and very honest and dependable. if you need someone with my qualifications, please let me know.
thank you very much for your kind attention.
sincerely yours,