Abstract
The paper reports the results of an in-depth crosslinguistic study of intervention effects and the grammar of
alternatives in a typologically diverse sample of five languages: Palestinian Arabic (Afro-Asiatic, Semitic), Russian
(Indo-European, Slavic), Samoan (Austronesian, Oceanic), Turkish (Altaic, Turkic), and Yoruba (Niger-Congo, Defoid). In all of
these languages, we find an interesting asymmetry in that focus evaluation interrupts question evaluation and causes an
intervention effect, but not vice versa. We take our data to inform the crosslinguistic analysis of two alternative-evaluating
operators, the squiggle operator and the question operator. To capture the observed absence of variation, we propose two semantic
universals: The squiggle operator unselectively evaluates all alternatives in its scope. The question operator, on the other hand,
is selective.