What 'accuracy' covers — and how errors cap your mark
The AO2 accuracy strand defined, and why sentence-boundary errors are the most expensive of all.
Section B is assessed on AO2 only — your written expression. AO2 has two strands, and ACCURACY is the first. It covers:
- Grammar — agreement (subject-verb), correct tense, consistent person and number, well-formed sentences.
- Punctuation — sentence boundaries (full stops, not comma splices), correct apostrophes, controlled commas, colons and semicolons used purposefully.
- Spelling — including the homophones that wreck meaning (their / there / they're; its / it's; affect / effect).
- Sentence control — sentences that are complete, deliberately shaped, and not accidentally run-on or fragmented.
Why accuracy is not a minor detail:
The mark scheme bands describe expression directly. At the top, Band 5 (21-25) is 'fluent, assured and consistently controlled'. At the bottom, Band 1-2 is 'basic and inaccurate' vocabulary with errors that impede meaning. The phrase impede meaning is the key: an error that makes the examiner stop and re-read costs you far more than a one-off slip they read straight past.
The cost hierarchy of errors (most expensive first):
| Error type | Why it costs the most |
|---|---|
| Sentence-boundary faults (comma splices, run-ons, fragments) | They make the writing hard to follow — they IMPEDE MEANING, the exact phrase that caps a script. |
| Tense and agreement drift | The reader loses track of when/who; repeated drift signals weak control across the whole piece. |
| Apostrophe and homophone errors | Frequent and visible; a script peppered with 'its/it's' and 'their/there' errors reads as careless. |
| Spelling of ordinary words | Less damaging singly, but a cluster of misspellings pulls a script out of the top band. |
The principle to memorise: Band 5 is not error-FREE writing — it is writing whose errors are rare and never impede meaning. You do not need perfection; you need control. The single most valuable accuracy habit is therefore not 'make no mistakes' but 'eliminate the errors that confuse the reader' — and those are almost always the sentence-boundary errors.
- AO2 accuracy = grammar, punctuation, spelling, sentence control.
- Band 5 expression is 'fluent, assured and consistently controlled'.
- Errors that IMPEDE MEANING cap the mark hardest — sentence boundaries first.
- You do not need perfection; you need control and few meaning-impeding errors.
- Cost hierarchy: boundary faults > tense/agreement > apostrophes/homophones > spelling.