Sentence: Say Irish advocates of a yes vote.

Im having a bit of a problem with this sentence!

“say Irish advocates of a yes vote”

Would you say that “of a yes vote” was the object of the sentence??

Also is it simple present?

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It is not a complete sentence, so I cannot comment on the verb tense.
‘Of a yes vote’ is a prepositional phrase, so cannot be the sentence object.
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okay, here is the whole sentence:

At stake for Ireland, say Irish advocates of a yes vote, is their country’s place in the EU. It either must remain at the heart of European decision-making or find itself isolated and friendless at the margin.

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At stake for Ireland…is their country’s place in the EU.– Main clause; S = place, V = is.

,say Irish advocates of a yes vote,– absolute dependent clause; S = advocates, V = say (simple present).
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