Language shapes how we navigate daily life, yet we rarely examine the building blocks we rely on. Among the most frequent terms in English, that functions as a pronoun, conjunction, and determiner. While it looks simple on the page, its linguistic versatility alters how we structure thoughts, connect with listeners, and process information.
Grammar textbooks often gloss over that as a minor functional word, but looking closer reveals a rich history and complex mechanics. We use it to specify objects, introduce clauses, and modulate emphasis without a second thought. Let's break down how this single linguistic element operates across different contexts and why it carries more weight than you might assume.
The Etymology and Evolution of the Word
To understand how that functions today, we have to look back at its origins. In Old English, the demonstrative pronoun system was far more complex than the modern version. The neuter singular demonstrative þæt served to point out specific items or refer back to previously mentioned concepts. Over centuries of phonetic shifts and grammatical restructuring, English simplified its gender and case inflections.
By the Middle English period, þæt evolved into the multi-purpose word we recognize. It absorbed functions that once belonged to several distinct pronouns and articles. Linguists track this shift as a process of grammaticalization, where lexical items turn into grammatical markers. Today, that acts as a linguistic chameleon, adjusting its job based on its position in a sentence. To get more information on this issue, extensive reporting can be read at The New York Times.
- Demonstrative Pronoun: Pointing out a specific entity ("Look at that").
- Demonstrative Determiner: Modifying a noun directly ("That car is fast").
- Relative Pronoun: Introducing a dependent clause ("The book that you lent me").
- Subordinating Conjunction: Linking a clause to a verb or adjective ("I knew that you would arrive").
Demonstrative Functions in Spatial and Mental Contexts
When used as a demonstrative, that establishes distance from the speaker. It pairs with this to create a spatial binary: this denotes proximity, while that denotes remoteness. Cognitive linguists note that this physical distinction bleeds into abstract thought.
When you say "That idea worked" instead of "This idea worked", you create psychological distance from the concept. Writers and speakers manipulate this distance intentionally. Advertisers use demonstratives to position products closer to the consumer's lifestyle, whereas cautious speakers use distance to remain objective.
Consider how children acquire this distinction. Research from Linguistic Society of America shows that children grasp proximal terms like this before mastering the contextual nuances of distal terms like that. Managing distance requires an understanding of shared perspective between speaker and listener.
The Mechanics of Relative Clauses
One of the heaviest lifting jobs for that is introducing relative clauses. It bridges an independent clause with descriptive information. For example, in the sentence "The report that was submitted yesterday contains errors", the clause led by that restricts the noun report.
Writers often debate whether to use that or which for relative clauses. Restrictive clauses—those essential to the meaning of the sentence—traditionally take that. Non-restrictive clauses—those offering extra commentary set off by commas—take which.
- Restrictive: The laptop that has a cracked screen belongs to Sam. (Identifies a specific laptop).
- Non-restrictive: The laptop, which I bought last year, works fine. (Adds extra information about a known laptop).
Ignoring this distinction leads to clunky prose. Streamlining your usage clears up ambiguities for readers who process complex sentence structures line by line.
Complement Clauses and Indirect Speech
Beyond pointing and relating, that functions as a complementizer. It introduces subordinate clauses that complete the meaning of verbs expressing thoughts, speech, or perception.
Think about sentences like:
- She believed that the project would succeed.
- He realized that time was running short.
In casual speech, we often omit this word: "She believed the project would succeed". This deletion speeds up delivery and feels more natural in conversational English. However, keeping or cutting that changes the rhythm of a paragraph. Formal writing often retains the conjunction to maintain precise syntax and signal a transition in thought.
Common Pitfalls in Daily Writing
Even native speakers stumble over the mechanics of that. Recognizing these common missteps improves overall writing clarity.
- Overuse in Close Proximity: Repeating the word multiple times in a single sentence creates jarring friction. "He said that that report was delayed" sounds awkward because two distinct grammatical functions collide. Rewriting to eliminate one instance fixes the flow.
- Confusing Who and That: When referring to people, standard grammar calls for who rather than that. Writing "The candidate that won the election" is common, but "The candidate who won the election" adheres closer to standard form.
- Unnecessary Inclusion: Cluttering sentences with extra conjunctions slows reading speed. Evaluate whether a sentence needs the conjunction or if dropping it creates a punchier delivery.
For broader insights on standard usage, check the Merriam-Webster Dictionary guide on grammatical terms and functional shifts.
Frequently Asked Questions
Is "that" always a pronoun?
No. While it frequently functions as a demonstrative or relative pronoun, it also serves as a demonstrative determiner ("that house"), a subordinating conjunction ("she knew that"), and even an adverb of degree ("it isn't that cold").
Can I always drop the word from a sentence?
Not always. You can safely omit it when it introduces a complement clause after verbs like think, say, or hope. However, you cannot drop it when it acts as the subject of a relative clause, such as in "The tool that broke the bench".
What is the difference between "this" and "that"?
The primary difference is proximity. This refers to items, ideas, or people close to the speaker in physical space or time. That refers to items or concepts further away, either literally or abstractly.
Why do some style guides prefer "which" over "that"?
Traditional American style guides, such as The Chicago Manual of Style, recommend reserving that for restrictive clauses and which for non-restrictive clauses. Following this rule helps clarify whether a clause defines a noun or merely adds parenthetical detail.
