When we talk, we say whole ideas: “The dog is barking.” “I ate my lunch.” When we write a whole idea, we call it a sentence.
A sentence has two jobs. It tells who or what the idea is about, and it tells what happens.
Key idea
A sentence tells a whole idea: who or what, and what happens.
Why it works
A reader can’t ask you what you meant. If you write only “The frog.”, the reader is left waiting: what about the frog? A whole sentence answers both questions, so the reader understands.
Worked example: Is it a sentence?
“The big red ball.”
- Who or what? The big red ball.
- What happens? It doesn’t say.
- It is only part of an idea, so it is not a sentence yet.
- We could finish it: “The big red ball rolls down the hill.”
Answer: Not yet. It needs what happens.
Common mistake
Thinking that a capital letter and a period make a sentence. “The big dog.” has both, but it is still only part of an idea. Check by asking the two questions: who or what? What happens?
For the grown-up. A sentence can be very short (“Birds sing.”) and a long string of words can still be unfinished. Read your child’s writing aloud with them and ask, “What happens?” when a sentence stops too soon. The site’s guides to The Mother Tongue begin the same way, with saying whole thoughts aloud before writing them.