  In codeswitching contexts, the language of a syntactic head determines the
distribution of its complements. Mahootian 1993 derives this generalization by
representing heads as the anchors of elementary trees in a lexicalized TAG.
However, not all codeswitching sequences are amenable to a head-complement
analysis. For instance, adnominal adjectives can occupy positions not available
to them in their own language, and the TAG derivation of such sequences must
use unanchored auxiliary trees. palabras heavy-duty `heavy-duty words'
(Spanish-English; Poplack 1980:584) taste lousy sana `very lousy taste'
(English-Swahili; Myers-Scotton 1993:29, (10)) Given the null hypothesis that
codeswitching and monolingual sequences are derived in an identical manner,
sequences like those above provide evidence that pure lexicalized TAGs are
inadequate for the description of natural language.
