Index - R
| R1 | Data.TagLabel |
| RB | Model.PennTreebank |
| RBR | Model.PennTreebank |
| RBS | Model.PennTreebank |
| REL | Model.UniversalTreebank |
| Rep | Data.TagLabel |
| Reparandum | Model.UniversalTreebank |
| reverseLabelMap | Data.TagLabel |
| ROOT | Model.UniversalTreebank |
| Root | Model.UniversalTreebank |
| rootLabel | Data.SyntaxTree, Data.ParsedSentence |
| RP | Model.PennTreebank |
| RRB_ | Model.PennTreebank |