昼夜

为了在规定时间内完成大桥的建设，工人们昼夜不停地施工。

To finish building the bridge within the required time, the workers are working around the clock.

这里的昼夜温差非常大，早晚出门需要多穿一件外套。

The temperature difference between day and night is very large here, so you need an extra layer when going out early or late.