This post highlights the use of that as a function word, which refers to what a word does as opposed to what it looks like (its of part of speech). Determining when that is optional versus when it is obligatory is a function of being concise and constructing semantically sound material. Below is an example of a direct speech from an online article that illustrates the importance of making such a determination:
I remember one point [Gayle King] said, “Don’t you just miss being around other people?”—Oprah Winfrey
Which of the following is the correct parse?
The first parse, which is correct, brings focus to the use of that as a complementizer, which turns the statement immediately after the main verb of the clause into an object (I remember [insert the sentence OBJECT here]). As illustrated in these examples, that could be placed in two different positions, which themselves are responsible for identifying the grammatical function of that.
Thus, what we are attempting to determine via parsing is what that as a function word does or the role that it plays. Therefore, the position of that in the arrangement of the sentence is a function of its syntactic function (the relationship to its constituent).
The second parse highlights that as a relativizer. I consider the following statement to be the best way to describe what a relativizer is. According to John Lawler, “Every relative clause contains an anaphor of its antecedent.” What the statement means is that that as a relativizer in a matrix clause is also an anaphor An anaphora is “The relation between a pronoun and its antecedent is called anaphora”: HUDDLESTON, R., & Pullum, G. K. (2005). Relative Clauses. In A Student’s Introduction … Continue reading, which points to its antecedent (a preceding noun/noun phrase or pronoun) that is the grammatical subject or object of an embedded clause (also called a subordinate clause). This structure, known as a complex NP, is illustrated via the example below. You may gain a deeper understanding of relativization via the principle of the Complex NP Constraint as explained in The Concise Oxford Dictionary of Linguistics.
In our two example parses above, the second is interpreted as a relative clause. (Note that the complex NP comes in two types: the relative clause and the NP complement.) Here is the second example again. However, an underscore (_) is used to represent something linguists call a filler-gap dependency. It refers to where the antecedent of that belongs in the embedded clause within the sentence.
I remember one point [(that)] Gayle King said_
However, this interpretation is unfortunate because here we can observe that such a parse does not yield to the semantics of the rest of the entire (original) sentence under consideration. Yet the reader could only come to this conclusion only after reading up to the comma (I remember one point [Gayle King] said,).
This outcome is called a “garden path” sentence, which you could read more about by following the link and going to the heading “Lack of proper clause-compounding that leads to parsing issues.” It forces the reader to backtrack to parse the sentence correctly, an outcome that would logically yield, as already illustrated, that the speaker, Oprah Winfrey, meant, or meant to say, the following:
I remember that (at) one point Gayle King said, “Don’t you just miss being around other people?”
Rather than potentially confuse your reader, pay attention to grammatical function. That as a function word can be absolutely essential to satisfy the requirements for syntax and/or semantics. Therefore, determining when that is obligatory or when it is optional (in which case it is called a zero relative pronoun) should be driven by the author’s desire to be concise and construct semantically sound material.
|↑1||An anaphora is “The relation between a pronoun and its antecedent is called anaphora”: HUDDLESTON, R., & Pullum, G. K. (2005). Relative Clauses. In A Student’s Introduction to English Grammar (p. 183). essay, Cambridge University Press.|
|↑2||You may gain a deeper understanding of relativization via the principle of the Complex NP Constraint as explained in The Concise Oxford Dictionary of Linguistics.|