The saying, "Everybody's business is nobody's business,"

“众人之事无人管”，

teaches us that in group work each person should be put in charge of a specific¹ part of the project.

这句话教导我们，在团队工作中，应指定每个人负责整个计划的某一特定部分。

If not everybody will think that somebody else is or will be doing it.

要不然每个人都会认为这件事有人在做或即将有人做。

In the long run, nothing will be done.

结果什么事也没做成。