With any container that you choose, you need to ensure that it allows the water in it to drain when necessary.

对于您选择的任何容器，您需要确保在需要的时候它能够排除里面的水。

youdao

They believe such a diet which includes no products from animal sources can be deficient in many of the necessary vitamins and minerals our bodies need.

他们认为，这样的饮食不包括任何动物来源的产品，会缺乏我们身体所需的许多必要的维生素和矿物质。

youdao

He's going to need to know the technical details of your system and acquire the specific equipment necessary for jamming your specific setup.

他需要了解你系统的技术性细节，并获得必要的特定设备来干扰你的特定程序。

youdao

"It is a promise that as long as I am your Commander in Chief, I will only send you into harm's way when it is absolutely necessary, and with the strategy, the well-defined goals, the equipment and the support you need to get the job done,"

VOA: standard.2009.05.22

Why don't bacteria need a distinct nucleus and that's necessary in a human cell?

为什么细菌不需要单独的细胞核,而对人类细胞则为必需

耶鲁公开课 - 生物医学工程探索课程节选

Some of the changes that are necessary need to take place, and the important steps that have to be demonstrated and the constitutional change that we need to see, that the people of Egypt need to see, on the road to free and fair elections.

WHITEHOUSE: Press Briefing

You also need procedures to implement the plan should it become necessary, and you need to revise the plan as your business changes.

FORBES: Disaster Recovery in the Cloud

If necessary, you need to re-brand and re-position your products and services.

FORBES: Can Groupon Succeed in China?