表达很愿意,可以用will, 只是表达将会,不带感情暗示用be going to 表示帮他但是他自己去做,用to do,表示帮助接手下来是你做,用in doing. 所以有以前方式:
I will help him I will help him to do it I will help him in doing it I am going to help him I am going to help him to do it I am going to help him in doing it