这时你需要停下来考虑你的目标，以决定哪个是更好的选择。

This is where you have to stop and reconnect with your goals to decide which is the better course.

youdao

对于前两种情况，你只能用简易型音频或视频无线器来演示文稿，这时你需要一份打印稿。

For the first two, you may have no choice but to go with an av free presentation, so have a printed copy of your notes with you.

youdao

在你的每周关注期间，如果你生活中的某个改变扰乱了该习惯，重返前一阶段，这时你需要更多的关注和精力来重新使之变成一种习惯。

If there's a change in your life that disrupts the habit, go back to the previous level, when you require more focus and energy to make it a habit again.

youdao

And resonance is the idea that sometimes one single Lewis structure does not adequately describe the electron configuration around a given molecule, so instead you need to draw two different Lewis structures to describe that more appropriately.

而所谓共振态,就是有时候一个路易斯结构不足以,完整描述一个给定分子的电子排布，因此这时你需要同时画出两个,不同的路易斯结构来描述它,这样会更恰当。

麻省理工公开课 - 化学原理课程节选