Dealing with Optional Complements in HPSG-Based Grammar ...

Figure 2: A sentence with three unrealized complements list of elements, all of which are optional (OPT plus) and unexpressed; the relevant type constraint and parts of the list hierarchy are shown in figure 3. list o list e or one list ne list e list o nelist one list one or more list o nelist ! 2 4HD unexpressed OPT plus TL o list 3 5 ................
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