请根据以下情景，用英语给马杰写封建议信。词数100左右。
Your best friend Ma jie is an outstanding basketball palyer in our school team, but now he is faced a problem. His parents require him to spend more time improving his grades. However, he has to spend more time working on his basketball skills. So, he doesn’t know how to solve the problem. He wants you to give him some advice.