01 The Four Legal Ways to Join Two ICs
Memorise these four — nothing else legally joins two ICs
1 · Period. IC. IC.   2 · Semicolon; IC; IC.   3 · Comma + FANBOYS (for, and, nor, but, or, yet, so): IC, and IC.   4 · Make one a DC with a subordinator (because, although, when…): DC, IC  /  IC DC.
02 The Three Boundary Errors
Run-on (fused)

× Two ICs jammed together with nothing: It rained the match was cancelled. Fix with any of the four joiners.

Comma splice (the most-tested error)

× Two ICs joined by a comma alone: It rained, the match was cancelled. A comma is not strong enough.

Fragment

× A piece missing a subject or main verb, or a stranded DC: Because it rained. Attach it to an IC.

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 02 Exercises →