问题补充：
It is said that the software on learning subjects for pupils in a very practical way.
A. designed
B. designing
C. are designed
D. is designed
答案：
A. designed
B. designing
C. are designed
(答案→)D. is designed
解析： 本句的主语是the software是一个单数名词，再根据前面的is说明本句使用一般现在时。句意：据说关于学生学习的软件是用一种特殊的方法被设计出来的。根据句意说明使用被动语态的形式。故D正确，
