Right node raising

In linguistics, the term right node raising (RNR) denotes a sharing mechanism that sees the material to the immediate right of parallel structures being in some sense "shared" by those parallel structures, e.g. [Sam likes] but [Fred dislikes] the debates. The parallel structures of RNR are typically the conjuncts of a coordinate structure, although the phenomenon is not limited to coordination, since it can also appear with parallel structures that do not involve coordination. The term right node raising itself is due to Postal (1974). Postal assumed that the parallel structures are complete clauses below the surface. The shared constituent was then raised rightward out of each conjunct of the coordinate structure and attached as a single constituent to the structure above the level of the conjuncts, hence "right node raising" was occurring in a literal sense. While the term right node raising survives, the actual analysis that Postal proposed is not (or no longer) widely accepted. RNR occurs in many languages, including English and related languages.

RNR is a phenomenon that challenges theories of syntax in significant ways. The difficulties are due to the status of the parallel structures as well as to the status of the shared material. The parallel structures typically do not qualify as constituents, and the shared material can also fail to qualify as a single constituent.

The following examples are typical instances of RNR in English. The square brackets mark the conjuncts of the coordinate structures involved and the material shared by the conjuncts is bolded:

One easily observable fact about these examples is that they prefer a unique intonation pattern. There tends to be emphasis on the contrasting words within the conjuncts and a pause immediately after the right-most conjunct and immediately before the shared material. This special intonation contour is sometimes indicated using commas, e.g. Fred prepares, and Susan eats, the food. A key observation about the conjuncts is that they are not constituents. Word combinations such as Fred prepares and Susan eats do not qualify as constituents in most theories of syntax. This fact casts doubt on the usefulness of coordination as a test for identifying the constituent structure of sentences.

The following subsections enumerate some noteworthy traits of RNR: 1) RNR is independent of coordination; 2) it occurs at various levels of structure (not just at the clausal level); 2) it is unlike instances of forward sharing in crucial respects; 4) the shared material can fail to qualify as a constituent; and 5) it at times requires the conjunct-final elements to stand in contrast to each other.

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