Sparks were emitted from small black boxes and red lamps flashed on and off angrily.

小黑盒子里迸出火花，红色灯泡发怒似地忽明忽暗。

If the light flashed on and off several times, the dolphins were supposed to press the left-hand lever followed by the right-hand one.

如果灯光是时不时的闪烁几下，那么海豚应该按压左手边的杠杆，然后是右手边。

This particularly infuriated Hermione, who was whiling away the wait for Kreacher by studying The Tales of Beedle the Bard and did not appreciate the way the lights kept flashing on and off.

这很明显地惹恼了正在读吟游诗人比德的故事的赫敏，她并不怎么喜欢灯光的忽明忽灭。