but none of them has been turned to stone yet.翻译出到目前为止是因为完成时还是因为yet
问题描述：
but none of them has been turned to stone yet.翻译出到目前为止是因为完成时还是因为yet
答
主要是因为现在完成时态.
现在完成时,其语法功能本身就是隐含着“谓语动作持续到现在/目前（为止）或对现在造成的影响”的意义,这里是后一种意思.yet加重了这种效果.
祝你更上一层楼!