They decided to put up an SOS sign.

他们决定升起求救信号。

youdao

Sure sign of hotel fatigue: coming back from breakfast I completely forgot my room number AND the name of the hotel I'm staying in…SOS!

毋庸置疑出现了旅馆疲劳迹象：吃完早餐回来，我完全不记得房间号码，甚至连住的酒店名称也忘记了……SOS！

youdao