这是他第一次使用纸牌策略。

This was the first time he'd used the card tactic.

youdao

youdao

当你和家人坐下来吃饭时，你有没有想过人们第一次使用筷子是在什么时候、什么地方？

When you sit down with your family to eat a meal, have you ever wondered when and where people used chopsticks for the first time?

youdao

If I want a copy of the string, I've got to whip out my week 1 skills of just iterating with a four loop from left to right and make copies of those characters.

我需要那个字符串的一个拷贝，我使用,第一周的技巧，从左到右做四次迭代,然后复制这4个字符。

哈佛公开课 - 计算机科学课程节选

You've probably heard it and use it many times.

你可能早就听说过，也使用过很多次了。

Let's 课堂 - SpeakingMax英语口语达人

But it's only an effective vaccine in the context where you have people who can go to the doctor's office, or to an urgent care, some kind of medical facility, three times, reliably, at a specified period of time.

但为了保证接种效果,人们必须亲自去诊疗室,或者在急诊室里,使用一些医学设施辅助接种,还需要接种三次,它只在一段时间内有效

耶鲁公开课 - 生物医学工程探索课程节选