地质学家们根据地球的演化历史，设计出一种特殊的地质年代表。

Geologists have devised a special geological time scale in reference to the earth's evolution.

youdao

地质学家们根据地球的演化历史，设计出一种特殊的地质年代表。

Geologists have devised a special geological time scale in reference to the earth's evolution.

youdao