Main and subordinate clauses
A clause is a group of words with a subject and a verb. A main clause gives a complete idea: "The girl smiled." A subordinate clause (also called a dependent clause) gives only part of an idea: "because she won". It cannot stand alone. It is joined to the main clause by a joining word such as who, that, when, where, because.
Each subordinate clause does one job in the sentence. It can describe a noun, act as an object, or tell us about the action. The rest of this lesson shows each job.
Attributive clause
An attributive clause (also called an adjective or relative clause) describes a noun. It answers "which one?" or "what kind?".
The girl who won the race smiled. (which girl?)
The book that I borrowed is old. (which book?)
The town where she was born is small. (which town?)
Joining words: who (people), which (things), that (people or things), whose (belonging), where (places). The clause comes right after the noun it describes.
Direct object clause
A direct object clause takes the place of a direct object. It answers "WHAT?" after verbs like say, think, know, hope, ask, tell.
She said that she was happy. (said what?)
I know where he lives. (know what?)
He asked if the shop was open. (asked what?)
Joining words: that (often left out: "I think it will rain"), if, whether, who, what, where, when, how.
Indirect and prepositional object clauses
An indirect object clause answers "to whom?" or "for whom?". It usually starts with who(m)ever: He gave whoever asked a sweet.
A prepositional object clause comes after a preposition (about, of, on, for, to...). It answers "about what?", "of what?":
They talked about what he said.
She is proud of what she built.
Give the ticket to whoever arrives first.
Tip: you cannot put "that" after a preposition. We say "proud of what she built", never "proud of that she built".
Clauses of place, time and manner
These are adverbial clauses: they tell us about the action in the main clause.
- Place (where?): We played where the road ends. Joining words: where, wherever.
- Time (when?): We left when the rain stopped. Joining words: when, while, before, after, until, as soon as.
- Manner (how?): He ran as if a dog was chasing him. Joining words: as, as if, as though, like.
These clauses can also come first: "When the rain stopped, we left." Then we put a comma after the clause.
Clauses of cause and purpose
Both answer "why?", but in different ways.
- Cause (reason): why something happened, already true. She was late because the bus broke down. Joining words: because, since, as.
- Purpose (aim): what something is done for, not yet happened. He studies hard so that he can become a doctor. Joining words: so that, in order that, lest.
Test: if you can say "and that is the reason", it is cause. If you can say "in order to", it is purpose.
Try it: add a green block
Start with a short blue sentence. Add one green block that answers where, when, why or which. Swap with a friend and name the type of each other's clause. Use the buttons in the 3D to check.
Key formulas and definitions
- Main clause + joining word + subordinate clause
- Which / what kind? โ attributive clause
- What? โ object clause (direct, indirect, or after a preposition)
- Where / when / how? โ clause of place / time / manner
- Why? โ cause (because) or purpose (so that)
Worked examples
1. Underline the subordinate clause and name it: "The man who lives next door is a doctor."
"who lives next door" describes the noun "man" (which man?). It is an attributive clause.
2. Name the clause: "I think that it will rain."
"that it will rain" answers "think what?". It is a direct object clause.
3. Name the clause: "Give the ticket to whoever arrives first."
"whoever arrives first" comes after the preposition "to" and answers "to whom?". It is a prepositional object clause.
4. Join with a time clause: "We will start. The guests arrive."
We will start when the guests arrive. ("when the guests arrive" answers when?)
5. Join with a purpose clause: "She saved money. She could buy a bicycle."
She saved money so that she could buy a bicycle. (the aim)
6. Cause or purpose? (a) He is tired because he ran ten kilometres. (b) He ran ten kilometres so that he would get fit.
(a) is cause: the running already happened and is the reason for being tired. (b) is purpose: getting fit is the aim of running.
Common mistakes
- Treating a subordinate clause as a full sentence: "Because she won." is only a fragment.
- Mixing up cause and purpose: because gives a reason, so that gives an aim.
- Putting "that" after a preposition. Use what or whoever: "proud of what she built".
- Forgetting the comma when the subordinate clause comes first: "When the rain stopped, we left."