as needed

基本解释

Grid provides an infrastructure that you turn it on and off as needed.
可以根据需要打开和关闭网格提供的基础设施。
You should expand on them to provide more error trapping and functionality as needed.
您应该根据需要扩展它们，以提供更多的防错措施和功能。
If the data set is large, do you have to send it all at once, or can you send pieces of it as needed?
如果数据集非常大，那么是必须同时发送完整的数据集，还是可以根据需要发送它的片段？

Also,the root can stay in the ground for as long as three years, so it can be harvested as needed.
By the way, after class, I'm more than happy to stay as long as needed to answer any questions you guys have or to talk about whatever issues you'd like to bring up, but probably what makes sense is for me to power down the computer and pack up and then we can stand out in the hallway and I can answer questions out there, that way the next class can get in and the instructor can work unimpeded.
顺便说一下,课后,我很乐意多待一会,来回答你们的问题,或者讨论一些你们提出的问题,但我最好是,把电脑关掉,收拾好东西,然后在走廊里来回答你们的问题,这样下节课才能照常进行,老师也能正常授课
耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选
and I knew if I wanted to be good, as good as I wanted to be, I needed to come here.
而且我知道，如果我想变得更好，变得和我想的一样好，我就得到这里来。
和纽约的留学生 - SpeakingMax英语口语达人

Banks normally loan money between themselves as needed by providing mortgages and other capital as collateral.
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