not necessary

基本解释

It’s not necessary, but it is a good practice to do so.
当然，这不是必须的，不过这样做是一个良好的习惯。
That is not necessary, whatsoever because being a minimalist is a loose definition in my opinion.
那是不必要的，因为我认为成为一个极简主义者是一个宽松的概念。
Serializable and thread-safe objects are not necessary if the object is put on the request, but then you will create a new instance of this class on every request, which might slow performance.
如果将对象放到请求中，那么可序列化和线程安全并不是必需的，但是您需要在每次请求中创建这个类的一个新的实例，这可能会降低性能。

He said the first great fact was that laws were not necessary to keep slavery out of California and New Mexico.
It's not necessary to do that, but it can be quite convenient.
虽然没有必要这样做，但是这样做是很方便的。
麻省理工公开课 - 热力学与动力学课程节选
It's not necessary very well formatted but it looks pretty complex, right?
排版不是很整齐,看起来也非常复杂，不是吗？
哈佛公开课 - 计算机科学课程节选

My assessment was this was not necessary in the situation but she could not see this.
FORBES: Getting In Our Own Way- Victims and Bullies