Dear Dad：
I am afraid that you will think me unpardonably negligent in not having answered your letter dated 7，December sooner，but when I have told you the reason，I trust you will be convinced that the neglect was excusable。
When your letter arrived，I was just in Hong Kong。 As my family could not forward it to me during my absence，it has been，therefore，lying on my desk until the moment when I took it up。 Now the first thing I have to hasten to do is to write to you these few lines to express my deep regret。
I enjoyed many pleasant sights during my trip。 I shall be pleased to give you an account to of them when I see you next。
Sincerely yours，
Tom