ebb
n. 衰退;退潮
vi. 衰退,衰落;(潮水或海水)退,落
例句
Morale among teachers is at a low ebb.
教师的精神面貌不佳。
《牛津词典》
As night fell, our enthusiasm began to ebb away.
我们的热情随着夜晚的降临而渐渐低落下来。
She sat in silence enjoying the ebb and flow of conversation.
她默默地坐在那儿,饶有兴致地听着时高时低的谈话声。