恩格斯在关于妇女问题的文艺论战中用以反对马果尔的文章是哪一部？
参考答案：《妇女问题和社会问题》
To tell the truth, what you said was too ________ for us to understand.
A．complex
B．comfortable
C．concrete
D．common
25x-30是方程．______．
