Without such tools, we have no reference points to indicate how far we have advanced or retreated.

没有这些工具，就没有参考点来标明我们进步了多少，退步了多少。

youdao

Without such tools, we have no reference points to indicate how far we have advanced or retreated.

没有这些工具，就没有参考点来标明我们进步了多少，退步了多少。

youdao