3. Syntax is the idea that word order helps convey meaning. For example, we know that “red fire engine” is different from “fire engine red.” We, as humans, have a set of rules about sentence structure. The sentence (or group of words) that we read is surface structure – there is no underlying meaning; it is simply what we see and perceive. The deep structure is the deep meaning and actual semantic identity associated with the sentence. Transformational grammar explains how two different deep structures can be expressed in a surface structure or how two different surface structures can be explained by one single deep structure. “Z ate an iguana” is an example of deep structure. This is the general concept behind the sentence. “An iguana was eaten by Zelda” is surface structure; the deep structure behind it is “Zelda ate the iguana.” “The shooting of the hunters was terrible” is an example of an ambiguous sentence. It can be explained by two possible deep structures – X shot the hunters or the hunters shot X.

4. There are a few types of sentence construction that are more difficult for people to process. One is the passive voice – the active form is more basic and the transformation to the passive form requires additional words. A study supports this; subjects were asked to report whether a sentence was plausible or likely. The subjects were highly accurate responding to sentences in the active voice, but accuracy dropped to about 75% when sentences were presented in the passive voice. Another difficult construction is a nested structure. This occurs when a phrase is embedded in another phrase, such as “The plane that I want to take leaves at 12 PM.” When reading this, we experience a “memory cost” – we have to remember the first part of the sentence while trying to process the rest.

5. Case grammar is another explanation for our rules about sentences. However, it is based on semantic roles; it states that we notice meaning changes, not changes in syntax. These roles include the agent (doer), relation (action), recipient (whom receives the relation), and the instrument (what the action is done with). The key to these sentences is the instrument. Garden Path sentences show that we tend to assign case roles on the line word by word. The principles of case grammar explain garden path sentences because it shows that we make assumptions about the first part of the sentence that are incompatible with the end of the sentence. In “The tenant delivered the junk mail threw it in the trash,” the tenant is actually the recipient, not the agent. People take longer to read GPS because they have to revise their case roles.