【正确答案】Dear Jerry,
I would like to know if I could ask for a casual leave of absence for one day on May. 18th.
This morning I received a letter from a friend of mine, inviting me to attend his wedding ceremony which will take place next Friday, May 18th. I am so pleased to learn this good news that I cannot wait to see my best friend becomes the happiest groom in the world.
I hope a one-day leave next Friday will not cause much trouble to you. You will be highly appreciated if you grant me my request.
Yours sincerely,
Wang Lin