Clause Type

There are several features that mark clause type.^30.2 They are:
mode
passive: possible values are +/- mode: possible values are base, ger, ind, inf, imp, nom, ppart, prep, sbjnct
The mode feature of a verb in its root form is base. The mode feature of a verb in its past participial form is ppart, the mode feature of a verb in its progressive/gerundive form is ger, the mode feature of a tensed verb is ind, and the mode feature of a verb in the imperative is imp. nom is the mode value of AP/NP predicative trees headed by a null copula. prep is the mode value of PP predicative trees headed by a null copula. Only the copula auxiliary tree, some sentential complement verbs (such as consider and raising verb auxiliary trees have nom/prep as the mode feature specification of their foot node. This allow them, and only them, to adjoin onto AP/NP/PP predicative trees with null copulas.