waste of time

基本解释

Attempting to change someone is a waste of time and energy.
尝试改变别人是一件浪费时间和精力的事情。
At the same time, other students in the same class already have the skill down cold, so further practice for them is a waste of time.
同时，同一个班级的其他学生可能已经熟练掌握了这项技能，所以继续练习对他们来说只是浪费时间。
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An architectural description, like any deliverable, needs to be created for a purpose and an audience, otherwise creating it is a waste of time.
一个架构描述，如同任何可交付的产品，是需要为了某个目标和受众而创建的，否则只是浪费时间。

In addition,news agencies provide updates and companies share product information through Twitter Some critics say Twitter is a waste of time that takes people's attention away from their work.
It was a complete waste of time, unless the goal in life was simply to pester the user for some input.
刚才的时间就完全浪费了，除非那个唯一的目的,是简单地纠缠用户索要一些输入。
哈佛公开课 - 计算机科学课程节选
The last one that we saw was a complete waste of time.
我们看的上一部这种电影完全是浪费时间。
There is no 实战 - SpeakingMax英语口语达人

This process might take hours or even days, and it is a complete waste of time!
FORBES: Stop Worrying About The Questions -Media Training