Movement

In syntax, movement is a process by which sentences end up spoken out loud in a different order than matches their underlying structure.

Generativist syntacticians say that sentences have a "deep structure" that adheres to universal grammar, but various language-specific constraints transform this into the "surface structure" when the sentence gets actually realized.

In English

For example, English has something called wh-movement: when we turn a sentence like Mary wants Bill to dance into a wh-question, we say Who does Mary want () to dance?

The generative explanation for this is that the question has a deep structure like Mary wants who to dance?, and then for pragmatic reasons, the question word moves to the front of the sentence and gets supported by "does". There is a trace marked by () in the spot where "who" moved from.

There is good evidence for these wh-traces. English speakers tend to agree that we can't contract the question to Who does Mary wanna dance? — we can imagine the wh-trace is there, unpronounced, but blocking the contraction.

Another example is inversion: in questions, auxiliary verbs move to the front of the sentence, like We should have told her → Should we () have told her? Again, the trace blocks contraction: Should we've /wiːv/ told her? sounds wrong.

In Toaq

Toaq's word order is VSO (verb-subject-object), but the Kuna output for a sentence like Noaq jí kúe nha indicates an SVO deep structure: jí noaq kúe. What's going on?

The generativist "verb phrase" has the verb and the object generated side-by-side. Even in VSO natural languages like Irish, there is evidence for verb-and-object VP structures. Meanwhile, there is also some evidence for verb-and-object structures in Toaq: for example, prepositional phrases like tî kúa, or object-incorporating verbs like po.

A generativist approach for analyzing a VSO language is thus that the verb and object really are side-by-side in the deep structure, and that the verb moves up to the front of the sentence for some reason.

A sentence with a serial verb, like Pu dıe tua sıq nháo jí máq, has a deep structure like Pu [nháo dıe [jí tua [sıq máq]]]. We say that there is an underlying Chinese-like nested SVO structure, but all verbs move to the tense ("V-to-T movement").

Toaq could have been designed as SVO from the start, and have a surface structure that's closer to the deep structure. There are aesthetic arguments in favor of VSO. For example, VSO grammar is similar to the logic notation $P(x,y,z)$ for predicates and their arguments.