“ESRI warns Irish recession to deepen next year”
All that’s missing is a menacing “or else”. Warn is traditionally a transitive verb (Pat warns Bob…) but developed intransitive use (Pat warns that/of/against…) about 100 years ago, according to Robert Burchfield in the third edition of Fowler’s Modern English Usage.
Warn is intransitive in the headline above, since the warning is delivered generally. Were it transitive, its direct object might be the public, the Government or everyone. It seems transitive because it’s followed immediately by “Irish recession”, which becomes its direct object in the absence of that. Reinstating that (here a subordinating conjunction) and other omitted elements:
[The] ESRI warns [that] [the] Irish recession [is] to deepen next year.
To maintain the headline form, it suffices to insert a comma or colon, and rearrange as necessary:
Irish recession to deepen next year, ESRI warns
ESRI warns: Irish recession to deepen next year
These re-worded examples are standard and quite unobjectionable. They convey the ESRI’s warning unambiguously, and are therefore immune to pedantic sarcasm.
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