Mistakes Grammarly Can Miss

Grammarly is an impressive artificial intelligence (AI) writing assistant. The software can even detect when text doesn’t match your desired tone and editing style, just like a professional proofreader.

However, Grammarly cannot understand what it is reading. Certain writing errors are only evident when you understand the meaning and context of the surrounding words.

So, what mistakes can Grammarly miss? 

Let’s put this AI proofreader to the test.

AI Proofreading Test

Here’s my passage of error-riddled text. How many mistakes can you find?

After baking in the oven for thirty minutes, Elaine removed the cookies. The sweet smell slowly filled the farmhouse. The sweet smell slowly filled the farmhouse. Minutes later, she heard the wooden stairs creaking continuously, and suddenly her 6 yr old grandson appeared. He squealed at the sight of the steaming cookies and rushed into the kitchen. 
Is it time to eat Grandma? Is it?
She laughed and put out her hand to stop him.
“Not yet, Jimmy, It will be another 15 minutes until they are cooled.”
Jimmy looked incredible. “Fifteen minutes! That’s so long!”

Grammarly’s Assessment

Now let’s see how many mistakes Grammarly can find.

Oops.

Grammarly didn’t find any mistakes!

The Mistakes Grammarly Missed

Now it’s my turn to proofread the passage. I’ll discuss the eight issues I see in order of their appearance. 

What went undetected?

Mistake One: Misplaced Modifier

The opening sentence contains the first culprit:

“After baking in the oven for thirty minutes, Elaine removed the cookies.”

Was Elaine baking in the oven, or were the cookies baking in the oven?

This error is an example of a misplaced modifier: a descriptive phrase (“modifier”) that is disconnected (“misplaced”) from what it describes, (“the cookies”). 

You and I can clearly see this is a mistake because we understand the difference in meaning.

There are multiple ways to clarify this sentence, but the simplest solution is to add one word.

“After baking them in the oven for thirty minutes, Elaine removed the cookies.”

Mistake Two: Duplicate Sentences

After baking in the oven for thirty minutes, Elaine removed the cookies. The sweet smell slowly filled the farmhouse. The sweet smell slowly filled the farmhouse. Minutes later, she heard the wooden stairs creaking continuously, and suddenly her 6 yr old grandson appeared. He squealed at the sight of the steaming cookies and rushed into the kitchen.

Duplicate words and even duplicate sentences are common to copy that has been edited several times. Since both sentences are grammatically correct, the only way the mistake shows up is if you are aware of the surrounding text.

Mistake Three: Inconsistent Numbers

After baking in the oven for thirty minutes, Elaine removed the cookies. The sweet smell slowly filled the farmhouse. The sweet smell slowly filled the farmhouse. Minutes later, she heard the wooden stairs creaking continuously, and suddenly her 6 yr old grandson appeared. He squealed at the sight of the steaming cookies and rushed into the kitchen. 
Is it time to eat Grandma? Is it?
She laughed and put out her hand to stop him.
“Not yet, Jimmy, It will be another 15 minutes until they are cooled.”
Jimmy looked incredible. “Fifteen minutes! That’s so long!”

The mixture of words and numerals for the numbers is less significant, but the inconsistency does look unprofessional and can be distracting.

Each major editing style has its own rules for when to use words or numerals. If this was an excerpt from a book, I’d follow the Chicago Manual of Style and spell out the numbers below 100.

Mistake Four: Inconsistent Tone

After baking in the oven for thirty minutes, Elaine removed the cookies. The sweet smell slowly filled the farmhouse. The sweet smell slowly filled the farmhouse. Minutes later, she heard the wooden stairs creaking continuously, and suddenly her 6 yr old grandson appeared. He squealed at the sight of the steaming cookies and rushed into the kitchen.

Here’s another mistake that looks unprofessional. The shorthand phrase “yr old” suits a text message, but it is too informal compared to the rest of the passage. This, again, only shows up in context. It should say “six-year-old.”

Mistake Five: Missing Punctuation

Is it time to eat Grandma? Is it?

“Is it time to eat Grandma” is a grammatically correct sentence, but based on the context, we know the boy wanted to eat cookies — not his grandma. That sentence urgently needs a comma before the word “Grandma.”

Also, this is a portion of dialogue, so it should be enclosed within quotation marks.

“Is it time to eat, Grandma? Is it?”

Phew. That’s much better.

Mistake Six: Incorrect Capitalization 

“Not yet, Jimmy, It will be another 15 minutes until they are cooled.”

The word “it” doesn’t start a new sentence, so either the “I” in “it” should be lowercase, or the comma after Jimmy should be replaced with a period.

“Not yet, Jimmy. It will be…”

“Not yet, Jimmy, it will be…”

Mistake Seven: Incorrect Word Usage

Jimmy looked incredible. “Fifteen minutes! That’s so long!”

“Jimmy looked incredible” is grammatically correct, but we know it doesn’t fit the context — Jimmy’s shock at the thought of waiting for 15 minutes. The adjective here was supposed to be “incredulous.”

Jimmy looked incredulous. “Fifteen minutes! That’s so long!”

Mistake Eight: Missing Paragraphing and Indentation

After baking in the oven for thirty minutes, Elaine removed the cookies. The sweet smell slowly filled the farmhouse. The sweet smell slowly filled the farmhouse. Minutes later, she heard the wooden stairs creaking continuously, and suddenly her 6 yr old grandson appeared. He squealed at the sight of the steaming cookies and rushed into the kitchen. 
Is it time to eat Grandma? Is it?
She laughed and put out her hand to stop him.
“Not yet, Jimmy, It will be another 15 minutes until they are cooled.”
Jimmy looked incredible. “Fifteen minutes! That’s so long!”

Grammarly didn’t flag the lack of line breaks or paragraph indents in the passage. 

The Corrected Passage

To review, here are all the corrections I would make.

Conclusion: Watch Out for Mistakes in Meaning and Context

Text that is grammatically sound can be confusing or ridiculous or even incorrect within the context of a passage of writing.

Grammarly is a time-saving tool, but it can’t yet replace a proofreader.