When the bottle had been uncorked and the wine poured out, like sunlight I watched it go down.
Since "had been " is omitted can I still say it is "predicate" ?
to my mind "had been" has been omitted simply to avoid repetition,which is quite common usage.
Although used elliptically here , since consisting only of the past participle , "poured out" still is the second predicate of the subordinate clause.
hope this helps
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