01 Semicolon = a soft period
IC on both sides
A semicolon joins two independent clauses: The vote passed; the law took effect at once. If either side cannot stand alone, the semicolon is wrong. (Its one other use: separating list items that already contain commas.)
02 Colon needs a complete sentence before it
Full sentence, then explanation or list
Whatever comes before a colon must be a complete sentence; what follows explains or lists it: She packed three things: a map, water, and a knife. × She packed: a map, water… — “She packed” alone is fine, but “She packed, such as:” style lead-ins fail the test.
03 Dashes — single and paired
One dash = a colon; two dashes = a pair of commas
A single dash works like a colon (complete clause before it): There was only one suspect—the butler. A pair of dashes works like a pair of commas around non-essential info — and a parenthetical opened with a dash must be closed with a dash, not a comma.
Ready to practice?

14 questions for this session — 4 guided (label the structure first), 6 on the clock, and 4 in home practice. Every timed score feeds your sub-skill Error Log.

Open Session 05 Exercises →