How do we know when a contrast is coming? This study explores the prediction of
parallel contrastive phrases, especially NPs, in sentences with and without overt focus
marking. A written sentence-completion questionnaire with clauses followed by the
conjunction “but” compared unmarked initial clauses to ones with the focus
marker “only” on the subject or object. Both conditions with
“only” elicited more contrasts overall than the condition without focus
marking, and many of the contrasts were with the focus-marked NP. While the baseline
(no-only) condition had full clauses for half of the completions, subject focus increased
clausal completions and object focus increased negative ellipsis completions
(“not”+NP structures), both changes in syntax which make a contrast with the
marked NP easy. The production of negative ellipsis sentences primarily in the
object-focus condition suggests that the object bias of these sentences in comprehension
could relate to their being used more frequently with this meaning. Finally, the overall
pattern of results shows that overt marking of contrastive focus increases continuations
with contrasts, and the conjunction “but” does not reliably predict
explicitly-stated contrasts within a sentence without overt focus marking.