Treat class like the active learning time that it should be.

要让课堂成为名副其实的主动学习时间。

Your active time reduces itself to three or four hours a day.

你的活动时间减少到每天三、四个小时。

Out of nearly 23,000 genes, over 5,000 were more active certain times of year.

在将近 23, 000 个基因中， 超过 5,000 个在一年中的某些时候更加活跃。

Mid to late August is the start of the most active and dangerous time for tropical cyclone activity.

8月中下旬是热带气旋活动最活跃、最危险的时期。

The Storm Prediction Center says April to June is the most active time for tornadoes in the U.S. and May is often the busiest month.

风暴预报中心说，4月到6月是美国龙卷风最活跃的时期，而5月通常是其中发生频率最高的一个月。

" Dusk is the most active time for many animal species in summer and is the best time to observe wildlife behavior, " said Yu Jinhua, a wildlife expert with the park.

“黄昏是夏季许多动物物种最活跃的时间，也是观察野生动物行为的最佳时间，”公园的野生动物专家余金华（音译）说。