前三个时期合起来持续了40亿年，合称为前寒武纪（隐生宙）。

The first three eons, which together lasted nearly 4 billion years, are together known as the Precambrian.

youdao

前三个时期合起来持续了40亿年，合称为前寒武纪（隐生宙）。

The first three eons, which together lasted nearly 4 billion years, are together known as the Precambrian.

youdao