可以说：
May I know the color of your story book?
Could I know the color of your story book?
Would you please inform me the color of your story book?
Would you please tell me the color of your story book?
Are you willing to inform me the color of your story book, please?
Are you willing to tell me the color of your story book, please?
What color is your story book, please?
都可以的
希望可以帮到你
望采纳