1. 建议他放弃这个想法； 2. 你的理由是：（1）容易染上坏习惯；（2）学习好坏的关键在于自身。
注意： 1. 信的格式已给出，不计入总词数； 2. 可以适当增加细节，以使行文连贯； 3. 词数：100左右。
4. 参考词汇：笔记本电脑 laptop computer；习惯habit
Thank you for your letter. To tell you the truth, I've thought a lot about whether you should buy a laptop computer to help you with your study. In my opinion, you'd better not. For one reason, it's very easy for you to develop some bad habits once you have it, such as playing computer games, seeing movies and so on, which will be a waste of time. For another reason, buying a laptop computer doesn't mean you can study well. If you want to make progress, you need to put your heart into your study and work hard. Whether you have a computer or not is not the most important.
Do you agree with me? Looking forward to your reply!