If you just scramble a sentence, it's pretty useless because the recipients are never going to be able to reverse the process.

如果你只是加密一个句子，这是毫无用处的,因为收件人没法将这个句子,反加密出来。

哈佛公开课 - 计算机科学课程节选

So it's almost as if functions really are useless because they have no ultimate effect.

所以几乎是函数是没起作用的,因为它们没有最终的效果。

哈佛公开课 - 计算机科学课程节选

It's missing all this stuff, so it must be useless.

它忽略了这么多东西,所以这个模型没有任何意义

耶鲁公开课 - 博弈论课程节选

It's just so vague as to be useless.

只是这些观点都太过模糊，没什么用。

耶鲁公开课 - 心理学导论课程节选

It's useless.

这收据没什么用。

斯坦福公开课 - Twitter之父Jack.Dorsey演讲：好奇和灵感的力量课程节选

Milton explains that the Licensing Order of 1643 is ineffective, it's useless because, and I'm quoting here, " order avails nothing to the suppressing of scandalous, seditious, and libellous books, which were mainly intended to be suppressed."

弥尔顿解释说《出版管制法》毫无作用，一无是处，我引用他的话说原因“,因为这个管制法对控制诽谤性的，有煽动性的，中伤他人的需要被控制的书籍毫无用处“

耶鲁公开课 - 弥尔顿课程节选

It's not a cyclical and useless definition.

这不是一个循环式的,没有意义的定义

耶鲁公开课 - 基础物理课程节选