员工看到的企业内部的变化通常是由()引发的。
参考答案:外部因素
向边长为a的正三角形内任投一点,点落在三角形内切圆内的概率是( )。
When the foreign guest arrived, I found him speaking good Chinese. I _______ his speech into
Chinese the night before. [ ]
A. needn't translate
B. didn't need to translate
C. needn't have translated
D. didn't need translating