Extra ambiguity from clausal mods

[emilymbender]

We found grammars with adverb-marked clausal mods giving extra ambiguity because the phrase structure rules for building PP out of S were underspecified for SUBORDINATED on the mother. Problem illustrated by grammar generated from attached choices file.
choices.txt

Relatedly, the left-coord-rule should have [ SUBORDINATED none ] in this type of grammar.