Schemata and principles are defined in the file "grammar/schema.lil"．The name of each schema is given in the file "grammar/types.lil"．
The following standard HPSG schemata are implemented．
| Schema | Name given to the schema in the definition file | Description |
|---|---|---|
| Head-Subject Schema | subj_head_schema | A verb takes a noun phrase as its subject |
| Head-Complement Schema | head_comp_schema | A verb or a preposition takes a noun phrase as its object |
| Head-Specifier Schema | spec_head_schema | A noun takes a determiner(an article or a demonstrative) |
| Head-Modifier Schema (left head) | head_mod_schema | The head is premodified by a modifier |
| Head-Modifier Schema (right head) | mod_head_schema | The head is postmodified by a modifier |
| Head-Filler Schema | filler_head_schema | Long distance dependencies |
Besides the above schemata, we have added the following schemata．
| Name given to the schema in the definition file | Description |
|---|---|
| head_relative_schema | A noun is modified by a relative clause |
| coord_right_schema | A conjunction takes its right conjunct as its argument |
| coord_left_schema | A conjunction takes its left conjunct as its arugment |
| empty_filler_head_schema | A relative clause takes an empty relative pronoun as its argument |
| empty_specifier_schema | ?A noun takes an empty specifier as its argument |
The following principles are implemented．
| Name given to the schema in the definition file | Description |
|---|---|
| head_feature_principle | The HEAD value of the head daughter is passed up to its mother |
| semantic_binary_principle | ?The CONT value of the head daughter is passed up to its mother. The CONT value of the non-head daughter is incorporated in the RELS list of its mother.非主辞の CONT は RELS に入る |
| semantic_unary_principle | The CONT value of the only daughter is passed up to its mother. |
| phonology_principle | The PHON value of all daughters are concatenated |
| adjacency_principle | The PROB_FEATURE|L_ADJAC feature contains information passed up from the left daughter whereas of PROP_FEATURE|R_ADJAC contains information passed up from the right daughter |
Besides the able principles, we have principles for passing information used by the statistical model．
Other principles in HPSG(such as the Valence Principle) are hard-coded as part of the above principles.