Dear Sir，
I am writing to inquire whether you will have any vacancies for a senior clerk in the near future。 I have heard that you hire senior clerk from time to time and I hope you will consider my application。 Please favour me with an interview if you think I might be acceptable。
I have been working in the library at Shue Yan College for two years。 I believe that my English is good enough for your needs。 My typing speed is about 75 words。 I am enclosing a resume for your reference。
Sincerely yours，