黑云母具有明显的多色性，当（）为棕黑色，当（）为浅黄色。
参考答案：解理缝平行下偏光振动方向；解理缝垂直下偏光振动方向
假设
--- Is there any possibility of the film _______ in Berlin International Festival?
--- Not in the least, because the audience generally think little of it.
A．trying out
B．tried out
C．to try out
D．being tried out
