未经制造厂批准，不得进行任何设计上的修改，也不得在车上（）。
参考答案：附加任何韧体
分解因式：n2-2n+1-m2=______．
The factory was built in a secret place, around ______ high mountains.
A．which was
B．it was
C．which were
D．them were
