Dear Penny,
Thank you for your letter. Sorry I haven't written for so long, I was busy at school. It's great that you're thinking about this job.
To my mind, it's not very difficult to work in a cafe. In fact, you shouldn't have any special skills. You should be polite, friendly and accurate when you serve people. But, to tell the truth, I suppose that you should have a part-time job. So I think that twenty hours a week will be enough. In fact, I believe that you'll enjoy this work as it's a good chance to meet new people and to have a work experirnce.
Sorry, but I have to go now.
Write back soon.
Best wishes,
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