"An illusory snake in a goblet" is used to describe the psychological state of being frightened caused by taking illusions as reality.
“杯弓蛇影”比喻把虚幻当作真实的恐惧心理。
In Jin Dynasty there was a man named Yue Guang who was fond of drinking alcohol.
晋朝有个叫乐(yuè)广的人，爱喝酒。
One day, he invited a friend to his house to drink together.
一天，他邀请朋友到家里来对斟（zhēn)对饮。
Suddenly, his friend saw the reflection of a snack swimming in the goblet.
忽然，朋友看见酒杯里有条蛇影在游动。
He got so much frightened that he took ill on bed after getting home.
他受了惊吓，回去便一病不起。
And neither any doctor or any medicine could cure his illness.
请医服药，都无起色。
Yue Guang came to see him and asked about the cause of his disease.
乐广跑来看他，问明起病的缘由。
When he got to know the cause, he pulled his friend from the bed immdiately and took him to his house.
乐广听后一把拉起朋友往家走。
Yue Guang made his friend sit where he used to, pouring a goblet of alcohol for him, and asked him," Is there any snake reflection in the goblet?"
他让朋友坐在原处，斟满酒问：“有蛇影吗？”
There was still a "snake reflection" in the goblet! Yue casually took away the bow hanging on the wall.
杯子里还有“蛇影”！乐广随手取下墙上的弓。
This time, the "snake reflection" disappeared.
这次，“蛇影”不见了！
"So it was the bow reflection that was in the goblet!" His friend at once got well from his illness.
“杯子里原来是弓影呀！”朋友的病情顿时好了！
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