Clauses, Conjunctions, and Relative Clauses

Overview

Complex grammar begins when we stop writing one isolated clause at a time and start connecting ideas. English does this through:

• coordination
• subordination
• relative clauses

These structures let us express contrast, reason, condition, time, concession, and added detail. They also help us avoid repetition.

Compare:

• The scientist gave a talk. The scientist won an international prize.
• The scientist, who won an international prize, gave a talk.

The second version is tighter and more natural because grammar helps combine the ideas.

Chapter Map

1. First, you will review the difference between independent and dependent clauses.
2. Then, you will study coordination and subordination.
3. After that, you will learn defining and non-defining relative clauses.
4. Finally, you will practice choosing clause structures for clarity and style.

Full Definitions

Independent clause

An independent clause can stand alone as a sentence.

Dependent clause

A dependent clause cannot stand alone and depends on another clause.

Conjunction

A conjunction joins words, phrases, or clauses.

Relative clause

A relative clause modifies a noun and usually begins with a relative word such as who, which, that, whose, where, or when.

Learning Objectives

• Distinguish independent and dependent clauses.
• Join clauses with coordinating and subordinating conjunctions.
• Build defining and non-defining relative clauses accurately.
• Choose suitable relative pronouns and omit them where natural.
• Use clause structure to create smoother, less repetitive writing.

The Big Idea

Clauses are not joined randomly. Each connection shows a relationship:

• addition
• contrast
• reason
• time
• condition
• concession
• definition

Grammar choices should make that relationship clear.

Section 1: Independent and Dependent Clauses

Example 1

• Independent clause: The seminar ended.

Example 2

• Dependent clause: because the seminar ended

Example 3

• Full sentence: We went for coffee because the seminar ended.

The dependent clause adds explanation, but the independent clause carries the sentence.

Section 2: Coordination

Coordination joins units of equal grammatical status.

Common coordinating conjunctions:

• and
• but
• or
• so
• yet
• for
• nor

Example 4

• Sentence: She revised carefully, and she passed comfortably.

Example 5

• Sentence: I wanted to stay, but I had another appointment.

Example 6

• Sentence: Hurry, or we will miss the start.

Use coordination when the ideas are balanced and equal.

Section 3: Subordination

Subordination makes one clause depend on another.

Common subordinating conjunctions:

• because
• although
• if
• when
• while
• since
• unless
• after
• before
• whereas

Example 7

• Sentence: We stayed inside because it was raining.

Example 8

• Sentence: Although she was exhausted, she finished the report.

Example 9

• Sentence: Call me when you arrive.

Subordination helps express hierarchy and logic.

Section 4: Choosing Between Coordination and Subordination

Example 10

• Coordinated: The weather changed, and the route became dangerous.
• Subordinated: When the weather changed, the route became dangerous.

Difference:

• coordination = two equal facts
• subordination = one fact gives the context for the other

Example 11

• Coordinated: He was tired, but he continued working.
• Subordinated: Although he was tired, he continued working.

The meaning is similar, but the tone and emphasis change.

Section 5: Relative Clauses

A relative clause adds information about a noun.

People

• who
• whom
• whose

Things and animals

• which
• that

Places and times

• where
• when

Example 12

• Sentence: The student who asked the question stayed after class.

Example 13

• Sentence: The article that I mentioned is online.

Example 14

• Sentence: The town where she grew up has changed a lot.

Section 6: Defining vs Non-Defining Relative Clauses

Defining relative clause

This clause identifies which person or thing you mean.

Example:

• The students who submitted late work must email me.

This means not all students, only that group.

Non-defining relative clause

This clause adds extra information. It is not necessary to identify the noun.

Example:

• My supervisor, who studied in Canada, encouraged me to apply.

This information is extra and is usually set off by commas.

Example 15

• Defining: The book that won the prize is on reserve.

Example 16

• Non-defining: This book, which won the prize last year, is on reserve.

Section 7: Who, Which, and That

Who

Used for people.

Which

Used for things, especially in non-defining clauses.

That

Often used in defining clauses for people or things in everyday English.

Example 17

• Sentence: The professor who teaches linguistics is absent.

Example 18

• Sentence: The software that we installed yesterday is already crashing.

Example 19

• Sentence: Her latest paper, which was published in March, has attracted attention.

Important note:

In non-defining relative clauses, that is generally not used.

Section 8: Relative Pronoun Omission

In some defining clauses, the relative pronoun can be omitted when it is the object, not the subject.

Example 20

• Full: The book that I borrowed is excellent.
• Reduced: The book I borrowed is excellent.

Example 21

• Cannot omit: The teacher who helped us stayed late.

Why:

• Here who is the subject of the relative clause.

Section 9: Whose, Where, and When

These often help writing sound more natural than heavy repeated nouns.

Example 22

• Sentence: I met a designer whose work I had admired for years.

Example 23

• Sentence: This is the building where the conference was held.

Example 24

• Sentence: Do you remember the day when we first met?

Section 10: Relative Clauses for Concision

Relative clauses help combine information smoothly.

Example 25

• Repetitive: I spoke to a student. The student had missed the deadline.
• Improved: I spoke to a student who had missed the deadline.

Example 26

• Repetitive: We visited a village. The village was rebuilt after the flood.
• Improved: We visited a village that had been rebuilt after the flood.

Section 11: Common Clause Problems

Run-on without a clear link

• WRONG: She was tired she finished the draft.

Overloaded subordination

Sometimes writers bury the main idea under too many dependent clauses.

Relative clause ambiguity

Example 27

• Unclear: I spoke to the manager of the branch that was closed.

Question:

• Was the branch closed, or was the manager of the branch closed? The noun attachment needs care.

Better:

• I spoke to the manager of the branch that had closed last month.

Common Mistakes and Why They Happen

Mistake 1

• WRONG: My brother, that lives in Delhi, is visiting.
• RIGHT: My brother, who lives in Delhi, is visiting.

Why learners make it:

• They use that in a non-defining clause.

Mistake 2

• WRONG: The people which work here are friendly.
• RIGHT: The people who work here are friendly.

Why learners make it:

• They confuse relative pronouns for people and things.

Mistake 3

• WRONG: The book who I bought is expensive.
• RIGHT: The book that I bought is expensive. / The book I bought is expensive.

Why learners make it:

• They choose the wrong relative pronoun for a thing.

Mistake 4

• WRONG: Although he was tired but he continued.
• RIGHT: Although he was tired, he continued. / He was tired, but he continued.

Why learners make it:

• They combine two linking systems at the same time.

Practice Plan

1. Identify independent and dependent clauses in ten sentences.
2. Join ten sentence pairs using coordination and then rewrite them with subordination.
3. Write ten defining relative clauses and five non-defining ones.
4. Decide where relative pronouns may be omitted.
5. Edit a paragraph to reduce repetition by using relative clauses.

Story Lab

”Story Lab: The Alumni Lecture”

“The university invited an alumna who now leads a climate research team in Singapore. She gave a lecture that focused on urban heat, water stress, and public policy. Students who had expected a technical presentation were surprised by how personal and practical her examples were.”

“After the lecture, several students stayed behind because they wanted career advice. One student, whose final project dealt with environmental data, asked a question that led to a long discussion. It was the kind of afternoon when a single talk changes the direction of future plans.”

What to notice

• who now leads… = defining clause about a person
• that focused… = defining clause about a thing
• who had expected… = defining clause narrowing a group
• whose final project… = possession inside a relative clause
• because they wanted… = subordinating clause showing reason
• when a single talk changes… = time clause used for reflective meaning

Final Summary

Clauses let writers connect ideas logically and efficiently. Coordination joins equal ideas. Subordination creates hierarchy and meaning relationships. Relative clauses add detail without repetition. Strong clause control makes writing smoother, denser, and more precise.

Mastery Checklist

You are ready to move on when you can do all of the following:

• distinguish independent from dependent clauses
• choose between coordination and subordination with a reason
• form defining and non-defining relative clauses accurately
• choose suitable relative words such as who, which, that, whose, where, and when
• use relative clauses to reduce repetition and improve flow