选择写作材料时应遵循的原则（）。
A、必要而充分
B、真实而准确
C、典型而新颖
参考答案：A, B, C
9.We still had a good harvest of wheat this year _______ the heavy drought in spring .
A．in spite of
B．due to
C．in case of
D．apart from
力比是示功图上单位（）长度所代表的载荷值。
