昙花一现 [- - yí xiàn]flower briefly as the broad-leaved epiphyllum; be a flash in the pan; last briefly; a nine days' wonder; like the morning dew; rare and brief appearance; vanish as soon as it appears:
•¶昙花一现的人物 a transient figure
•¶ 他们不过是历史舞台上昙花一现的人物。 They are merely passers-by on the stage of history.