The 15 Most Common Mistakes in Fiction Drafts, According to Our Checker
The most common grammar mistakes in fiction drafts are not spelling errors but narrative grammar errors: a tense that slips from past to present, a dialogue tag punctuated like a sentence, a modifier hanging off the wrong subject, two actions that cannot physically happen at once. These are the fifteen the checker in the Sagoræ workshop underlines most often in drafts, with no ranked figures (texts are private; only the nature of the errors is observed). For each one: the faulty sentence in italics, the fix, the rule. The built-in checker, no AI, free and unlimited, catches them; the AI Checker explains why; the rule is yours to keep.
Five tense and sentence-structure mistakes
1. The tense slip. Before: He set the bag down. He looks at the window. After: He set the bag down. He looked at the window. Rule: a narrative picks its base tense and keeps it. Present tense inside a past-tense narrative belongs only in dialogue. The choice itself is covered in past or present tense for your novel.
2. Past perfect that never ends. Before: She had opened the letter. She had read it twice. She had put it back. After: She had opened the letter. She read it twice and put it back. Rule: use "had" once to step into the flashback, then return to simple past. A whole paragraph of "had" reads like a ledger.
3. The dangling modifier. Before: Walking into the kitchen, the envelope was still on the table. After: Walking into the kitchen, she saw the envelope still on the table. Rule: the phrase before the comma describes the subject that follows it. Envelopes do not walk.
4. Impossible simultaneous actions. Before: Opening the drawer, he crossed the room. After: He crossed the room and opened the drawer. Rule: "-ing" clauses mean "at the same time". Two actions that happen in sequence take "and" or two sentences.
5. The comma splice. Before: It was raining, she did not have an umbrella. After: It was raining. She did not have an umbrella. Rule: two independent clauses need a full stop, a semicolon or a conjunction. A comma alone will not hold them.
Five dialogue and punctuation mistakes
6. The full stop before a tag. Before: "Do you have a light." she asked. After: "Do you have a light?" she asked. Rule: a tag continues the sentence, so the line ends with a comma, a question mark or an exclamation mark inside the closing quotation mark, never a full stop.
7. The capital after a question mark. Before: "Do you have a light?" She asked. After: "Do you have a light?" she asked. Rule: the tag that follows a line of dialogue starts lowercase, even after a question mark or an exclamation mark.
8. The verb that cannot speak. Before: "No," she smiled. After: "No." She smiled. Rule: you cannot smile a word. A tag takes a speech verb; a gesture goes in its own sentence, as an action beat.
9. Two speakers in one paragraph. Before: "Do you have a light?" "No smoking in here," he said. After: a new paragraph for each speaker. Rule: one speaker per paragraph. The line break is what tells the reader who is talking when tags are dropped. The full conventions, including how they differ in French, are in how to punctuate dialogue.
10. The hyphen doing a dash's job. Before: a hyphen with spaces around it used as a pause. After: an em dash or, better in most manuscripts, a colon or a pair of commas. Rule: the hyphen joins two words; it does not interrupt a sentence. Word processors do not always convert it.
Five word mistakes
11. Lay and lie. Before: She laid on the bed. After: She lay on the bed. Rule: "lie" takes no object (lie, lay, lain); "lay" needs one (lay, laid, laid). She lay down; she laid the envelope down.
12. Its and it's. Before: The hotel had lost it's night porter. After: The hotel had lost its night porter. Rule: "it's" is always "it is" or "it has". The possessive has no apostrophe, like "his" and "hers".
13. Could of. Before: He could of asked. After: He could have asked. Rule: the sound of "could've" hides "have". The same goes for should, would and might.
14. Fewer and less. Before: Less guests than last Thursday. After: Fewer guests than last Thursday. Rule: "fewer" for things you can count, "less" for quantities you cannot. Fewer letters, less mail.
15. Numbers in figures inside narrative. Before: She was on day 90. After: She was on day ninety. Rule: in narrative, numbers are spelled out up to one hundred; figures stay for dates, times and room numbers. One convention, kept from chapter 1 to the end.
What the checker sees, what it explains
The built-in checker underlines all fifteen while you write. What a classic checker does not do, and what the AI Checker adds on a finished chapter, is the reason: the modifier attaches to the envelope because the envelope is the subject of the main clause, rather than a bare underline. It does not replace the word; it shows you the rule, and by the third time you no longer see it underlined. To compare what different tools catch on a piece of fiction, read the comparison of grammar checkers for fiction writers.
C The Proofreader · Spelling, grammar, typography Pre-recorded demo
The Proofreader reviews a paragraph from chapter 3
The Proofreader
Five suggestions, to accept or reject one by one:
- grandmothers → grandmother's: possessive apostrophe.
- was creaking → were creaking: the subject is "the shutters".
- answer , → answer,: no space before the comma.
- did not answer, she was looking → did not answer; she was looking: two independent clauses, a comma splice.
- turning round : fine in British English; switch to "turning around" only if the rest of the novel is in American English.
I am leaving "at the slightest wind" alone: it is correct, and it is your rhythm.
The Proofreader
Understood: comma splices in dialogue-adjacent narration are added to your style exceptions for this novel, I will not flag them again. Four fixes applied, the paragraph is still yours.
Pre-recorded simulation. The built-in proofreader is free and unlimited; it suggests, the author accepts or rejects each fix.
These fifteen mistakes map to points 27 to 36 of the 40-point self-editing checklist, the sentence-pass points, to be checked last.
Frequently asked questions
What is the most common grammar mistake in a manuscript? The tense slip, closely followed by the dialogue tag punctuated with a full stop. Both go unnoticed on rereading because the sentence sounds right.
Does a standard spellchecker catch these? Mistakes 12, 13, 14 and 15, yes. Tense consistency (1, 2), sentence structure (3, 4, 5) and dialogue (6 to 10) need a checker that reads the narrative, not just the sentence.
Should I fix mistakes as I write or at the end? Let the checker underline while you write, it costs nothing, but do the real sentence pass last, once the text has stopped moving.
If you want these fifteen mistakes underlined and explained without a single word being changed for you, Sagoræ offers a free trial, no card required.
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