| Mark | Meaning |
| Agr | Agreement error: subject/verb or pronoun/antecedent |
| Awk | Awkward construction or phrasing |
| CS | Comma splice (the writer has incorrectly put two main clauses/sentences together with only a comma) |
| EX | Examples: the writer needs to provide examples |
| Frag | Sentence fragment |
| Mod | Modifier: the writer has a misplaced or dangling modifier |
| P | Punctuation error |
| Pass | Ineffective use of passive voice |
| PL | Faulty parallelism: construction is not parallel (// symbol can also be used to indicate this fault) |
| RO | Run on sentence |
| Sp | Spelling error |
| T | Tense: the writer has used the wrong tense or has tense shifts |
| Trans | Transition: the writer needs transitions between paragraphs or ideas |
| TS | Topic sentence or thesis statement: the editor recognizes a problem with the TS, or one does not exist |
| US | Usage: The writer has made an error in language usage |
| WC | Word choice: the editor questions the use of a particular word for style or appropriateness |
