π Understanding Relative Clauses: That vs. Which
Relative clauses add extra information to a noun in a sentence. 'That' and 'which' are relative pronouns that introduce these clauses, but they aren't interchangeable. The key difference lies in whether the clause is essential (restrictive) or non-essential (non-restrictive).
π Defining 'That' Clauses
A 'that' clause is a restrictive (or essential) relative clause. This means the information it provides is vital to understanding which noun is being referred to. Without it, the sentence's meaning would be unclear or incomplete.
π Defining 'Which' Clauses
A 'which' clause is a non-restrictive (or non-essential) relative clause. This means the information it provides is extra, but not necessary, to understand the sentence. It adds detail but doesn't limit or define the noun. These clauses are always set off by commas.
| Feature | 'That' Clause | 'Which' Clause |
|---|
| Type | Restrictive (Essential) | Non-restrictive (Non-essential) |
| Necessity | Provides essential information to identify the noun. | Adds extra, non-essential information. |
| Commas | Never uses commas. | Always uses commas. |
| Effect on Meaning | Changes the fundamental meaning of the sentence if removed. | Does not change the fundamental meaning of the sentence if removed. |
| Formality | Generally considered more formal. | Generally considered less formal. |
| Example | The book that I borrowed from the library is overdue. | The book, which I found on the top shelf, is a first edition. |
π Key Takeaways
- π― Essential vs. Non-Essential: Determine if the clause is necessary to identify the noun. If it is, use 'that'. If it just adds extra info, use 'which' with commas.
- βοΈ Comma Usage: Remember, 'which' clauses always need commas, while 'that' clauses never do.
- π‘ Sentence Meaning: Try removing the clause. Does the core meaning of the sentence stay the same? If yes, it's likely a 'which' clause.
- π AP Lang Tip: Correctly using 'that' and 'which' showcases your attention to detail and understanding of grammar, impressing your graders.