Regular repeating actions such as sound waves, light waves, or radio waves have a certain frequency, or number of waves per second.

有规律的重复活动如声波、光波、无线电波都有一个特定的频率，或者说是每秒的波动次数。

《柯林斯英汉双解大词典》

The second problem is that Venus exhibits a halo of light when it is seen just outside the Sun's disc.

第二个问题是，当金星在太阳圆盘外被观测到时，它会呈现出光晕。

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The second student said his eyes were full of light green.

第二个学生说他的眼睛充满了浅绿色。

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And then we have c, the speed of light, 2.998 times 10 to the 8 meters per second.

然后我们知道光速等于，2，998乘以10的8次方米每秒。

麻省理工公开课 - 化学原理课程节选

You get 2.18 times 10 to the plus 6 meters per second, 1% which is about 1% of the value of the speed of light.

。18*10^6米每秒，得到的速度大概是光速的。

麻省理工公开课 - 固态化学导论课程节选

We'll turn the light back on for a second here.

我们马上要开灯。

麻省理工公开课 - 化学原理课程节选

Research demonstrates that red light problems at intersections can be corrected simply by extending the duration of the yellow light a second or two.

FORBES: OUT OF FOCUS

Gretzky then made his way to the harbour to light a second cauldron outside in the harbour area which will burn for the 17 days of competition.

BBC: Winter Olympics start despite luge tragedy

United travel to the Stadium of Light in second place, having closed the gap on Chelsea to three points - despite only drawing at Bolton - after Carlo Ancelotti's side lost to Manchester City.

BBC: No panic over Manchester United form - Rio Ferdinand