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📘 Two red letters in the margin

Your story comes back with two little codes in the margin: frag and R.O. The teacher did not write “bad writing.” Those marks mean something smaller and more useful. Frag is short for fragment: a piece that looks like a sentence but is not

5
lessons
~25 min
to learn
Adults
level
Start the course →

What you’ll learn

  1. What a sentence needsName the three parts of a complete sentence and tell a leftover from a finished thought.A sentence needs a subject, a verb, and a thought that can stand alone. Length does not decide. Two words can be a sentence; a long leftover is still a leftover.
  2. When a sentence is missing a pieceSpot fragments that lack a subject, lack a verb, or lean on words such as because, when, and if.Fragments are unfinished jobs. Add the missing who or do, or attach the leaner to a sentence that can stand. Do not leave because, when, or if holding a full stop alone.
  3. When two sentences crashTell a fused sentence from a comma splice and explain why a comma alone is not a legal join.A run-on puts two complete sentences on one track without a legal hinge. No mark at all is a fused sentence. A comma alone is a comma splice. Closeness is not a join.
  4. Three honest repairsRepair a run-on by splitting, by using a comma plus a FANBOYS word, or by making one idea lean on purpose.A full stop makes neighbours. A comma plus and, but, or so makes partners. Because, when, and if rank one idea under the other. Choose the hinge that matches the relationship.
  5. Catching them on the pageUse reading aloud and a yes-or-no question test to find fragments and run-ons in a real draft.Your voice trips where the punctuation should. The yes-or-no test shows whether a line is one thought or two. Repair is mechanical: find each engine, then write the hinge.

Questions this course answers

Which line is a complete sentence?

“The fox jumped.” has a subject, a verb, and a finished thought. The other three are leftovers: a leaner, a missing who, and a missing do.

Match each leftover to what it is missing.

Fragments fail in different ways. Some have no who, some have no do, and some have both but still lean on a joining word such as because.

Put these steps in order to fix “Because the bus was late.”

A because-clause is not trash. Spot the lean, give it a landing, join the chunks, then listen.

Which line is a comma splice?

A comma splice joins two complete sentences with a comma and nothing else. Adding so, using a full stop, or making one clause lean are all legal.

Name the memory trick for the seven coordinating conjunctions.

FANBOYS stands for for, and, nor, but, or, yet, so. A comma plus one of these can legally join two complete sentences.

In your own words, why is “The rain started, we ran.” not a legal sentence even though it has a comma?

The comma looks like a join, but two independent clauses need a stronger hinge: a full stop, or a comma plus and/but/so, or a leaning word.

Grounded in trusted sources

  • Purdue Online Writing Lab, Sentence Fragments, https://owl.purdue.edu/owl/general_writing/mechanics/sentence_fragments.html
  • Purdue Online Writing Lab, Run-ons — Comma Splices — Fused Sentences, https://owl.purdue.edu/owl/general_writing/punctuation/independent_and_dependent_clauses/runonsentences.html
  • The Writing Center, University of North Carolina at Chapel Hill, Fragments and Run-ons, https://writingcenter.unc.edu/tips-and-tools/fragments-and-run-ons/
  • Common Core State Standards Initiative, CCSS.ELA-Literacy.L.4.1.f and L.4.2.c, https://www.thecorestandards.org/ELA-Literacy/L/4/
  • Anna Mills, How Arguments Work, 13.5 Run-on Sentences, Humanities LibreTexts, https://human.libretexts.org/Bookshelves/Composition/Advanced_Composition/How_Arguments_Work_-_A_Guide_to_Writing_and_Analyzing_Texts_in_College_(Mills)/13%3A_Correcting_Grammar_and_Punctuation/13.05%3A_Run-on_Sentences
  • Kashyap and Dyquisto, 12.20 Run-On Sentences and Fragments, Humanities LibreTexts, https://human.libretexts.org/Courses/City_College_of_San_Francisco/Writing_Reading_and_College_Success%3A_A_First-Year_Composition_Course_for_All_Learners_(Kashyap_and_Dyquisto)/12%3A_Grammar/12.20%3A_Run-On_Sentences_and_Fragments
  • Department for Education, National curriculum in England: English programmes of study, https://www.gov.uk/government/publications/national-curriculum-in-england-english-programmes-of-study/national-curriculum-in-england-english-programmes-of-study

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