Grammar Error Detective Lab
Read a passage, click the phrases you think contain a grammar error, then reveal the actual errors with explanations and corrections. Practice spotting run-ons, comma splices, subject-verb agreement mistakes, apostrophe misuse, fragments, and misplaced modifiers.
Guided Experiment: Spot the Grammar Errors
Hypothesis
Setup
Run Experiment
Analyze
Conclude
Which passage do you think has the most grammar errors, and why?
Write your hypothesis in the Lab Report panel, then click Next.
Controls
Sentence Hints
- Sentence 1: 1 error
- Sentence 2: 2 errors
Passage
Me and my brother went to the store, we bought some snacks for the movie. The dog were happy to see us, it's tail wagged with joy.
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Reference Guide
6 Error Types to Watch For
- Run-on. Two complete sentences fused with no punctuation or conjunction.
- Comma splice. Two independent clauses joined only by a comma.
- Subject-verb agreement. The verb form does not match a singular or plural subject.
- Apostrophe misuse. A contraction and a possessive are mixed up, such as "it's" and "its."
- Fragment. An incomplete sentence punctuated as if it were complete.
- Misplaced modifier. A descriptive phrase attached to the wrong noun.
How to Use This Lab
- Pick a passage and a difficulty level.
- Click any phrase you think contains a grammar error.
- Reveal the answers and compare to the explanations and corrections.
- Record your findings in the lab report below.
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