English Grammar Review
Clauses and Punctuation
There are three kinds of dependent clauses: noun, adjective, and adverb.
An adjective dependent clause can function as an adjective in a sentence:
Kayla wrote the best analysis.
Kayla wrote the analysis that was the best.
Adjective clauses are usually placed after the noun they modify.
Most adjective clauses are introduced by one of the relative pronouns, that, which, who, whom.
The terms which Tafadzwa agreed on will not change.
[clause modifies terms]
Contact the person who is responsible in Zimbabwe.
[clause modifies person]
New hires whom you supervise should attend.
[clause modifies hires]
Sometimes the adjective clause does not need to start with the relative pronoun.
The terms (which) Tafadzwa agreed on will not change.
Contact the person (who is) responsible in Zimbabwe.
New hires (whom) you supervise should attend.
These are still adjective clauses, with the relative pronoun implied.
Some adjective clauses are introduced by the relative adjective whose or by one of the relative adverbs, where, when, why.
The owner whose building we rented was not present.
[clause modifies owner]
That was the building where we started.
[clause modifies building]
This is the day when we sign the new lease in Bulawayo.
[clause modifies day]
The investors from Harare told us the reason why we had to change.
[clause modifies reason]
Again, sometimes the adjective clause does not need to start with the relative adverb.
This is the day (when) we sign the new lease in Bulawayo.
The investors from Harare told us the reason (why) we had to change.
Adjective clauses and punctuation
Question: When should an adjective clause be surrounded by commas?
Answer: When the information in the clause does not change the basic meaning of the sentence.
Mr. Mbangwa decided that last week's pizza, which has gone stale in the refrigerator, should be thrown out.
Exception: When the clause begins with the word that.
Mr. Mbangwa decided that the pizza that has gone stale in the refrigerator should be thrown out.
Note: Surrounding commas are used for noun clauses that are used in apposition when the information in the clause is not essential to the meaning of sentence, even when the clause starts with the word that.
Mr. Mbangwa's decision, that the stale pizza should be thrown out, was not surprising.
Here the clause is not modifying the noun decision, so it is not an adjective clause. Instead, it is a noun clause that apposes or restates the noun. And it is not strictly essential, so we set it off with commas.
Lesson: Dependent Adjective Clauses
Module: Clauses and Punctuation
Course: English Grammar Review