twilight, dawn, dusk, nightfall这些名词含有“黎明，黄昏”之意。

(1) twilight：指日落后或日出前的微明，但通常侧重于前者——黄昏;薄暮

They returned at twilight, and set off for one of the promenade bars. 他们黄昏时分回来，然后去了一家步行街酒吧。

(2) dawn：指天刚亮时的黎明，可作引申用——黎明;拂晓

Nancy woke at dawn. 拂晓时分南希醒了。

(3) dusk：指接近夜晚的黄昏时刻——黄昏;傍晚;薄暮

We arrived home at dusk. 我们傍晚到家。

She turned and disappeared into the dusk. 她转身消失在暮色中。

(4) dawn：表示天变黑的前一段时间——黄昏;傍晚;日暮

I need to get to Lyon by nightfall. 我需要在黄昏前到达里昂。

I started work at dawn and returned only at nightfall. 我披星戴月地工作。