I have learned that you are successfully admitted to your target university, so I am writing to present you my hearty congratulations。
There are several factors accounting for this letter. On one thing, I would like to suggest that you make full preparations for the first lesson of your university life, the coming military training, which is fairly energy-demanding and physically challenging. For another, English will still be very important when you are a college student. Thus it is strongly recommended that you continue to learn English during this vacation。
It is my sincere hope that the above advice will be of any help to you. And wish you a splendid university life!