It has remained virtually unchanged since time immemorial.

它几乎自古以来都维持不变。

From time immemorial man has approached woman with his proposal and has requested conjugality from her.

自古以来，男人就向女人求婚，并要求夫妇生活。

It's been like that since time immemorial.

自古以来就是这样。

And that has continued from time immemorial.

自古以来，这就一直延续下去。

My family has lived in this area from time immemorial.

我的家族在这个地区已经生活了不知有多少年了。