Turn left at the first robot.

在第一个交通信号灯处向左拐。

《牛津词典》

At the first hint of trouble, they left.

他们一发现有点不妙的迹象就离开了。

《牛津词典》

At the first gunshot, the crowd scattered.

枪声一响，人群便逃散了。

《牛津词典》

As histories tell it,he looked and looked at the first photograph, and said: "This is one for all time."

VOA: special.2010.05.31

And if that's true is everything in the string, starting at the first element and removing the last element, a palindrome?

如果是相同的话,是不是字符串中的所有从第一个元素开始,并且删除最后一个元素后？

麻省理工公开课 - 计算机科学及编程导论课程节选

Well it'll be interesting to see if you swing at the first pitch and decide to take this class on.

我很希望大家能,上了试听课后,继续选修这门课

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

At the first sign of a strengthening dollar, you should sell the bond, she says.

FORBES: The Global Test

Now, that cooperation was on display yesterday at the first G20 summit in an Asia Pacific nation.

WHITEHOUSE: President Addresses CEO Business Summit

"I'm aiming to drive the car at the first test, " Webber told BBC Sport.

BBC: Webber targets return in February