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转告 (zhuǎngào) — pass on a brief message;
转述 — retell or paraphrase a longer statement, often preserving content but not exact wording. Grammatically,
转 here is the "transfer/pass on" sense (same as in
转交 "hand over,"
转发 "forward [a message]"). The English-grammar term "reported speech / indirect speech" is rendered as
转述 in Chinese textbooks.