describe the situation; Explain why you cannot continue at this time; Say what action you would like to take

Dear Mr. Anderson, I am writing this letter to explain my absence from the classes in the past few days. As you are aware, I have a full-time job at Berkley street. Recently the workloadhas increased threefoldand there is no definite time for me to leave from the office. Hencemy absence for the past few days. Thus, I regret to inform you that I won't be able to continue with my evening classes. The situation is already very taxing with the current workload. Moreover, the travel time from my office to your institute is well over an hour, not to forget the maddening rush on public transport during these hours. This leaves me totally exhausted and incapable of being productive. However, I wanted to enquire whether is there any possibility to access the course online?  This way, I could mitigate my concerns, without losing out on doing the course and this would also provide a new medium for you to reach more students, who are not able to attend any coursesdue to hectic work life. I have been researching such tools for the past few days and I do have a recommendation for you. I am attaching all the relevant details about this tool along with this mail. Yours truly, Nathan Jones