Dear Mum,
I want to say 'thank you' to you. From the day you brought me into this world, you have made sacrifices for me. You taught me how to be a good person. If it weren't for you I would never have existed.
I also want to tell you I love you, but I am a little shy. How can I say this to you? Well, from now on, I will do my best. I will study hard and help you at home. I will never get angry when you tell me what to do.
I hope I can look after you in your old age, just like you've looked after me. Thank you, Mum.
一共是116字.可以吗?英语是我的母语,所以你最好加一些错误,不然你的老师会知道^ ^