To be scared by imaginary fears; to be overly suspicious and cause oneself unnecessary anxiety, like mistaking the reflection of a bow in a cup for a snake.
小明因为杯影蛇弓，总觉得宿舍里有人故意针对他，弄得他寝食难安
Xiao Ming was so scared by imaginary fears that he always felt someone in the dormitory was deliberately targeting him, which made him restless.
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