ACT Preparation / Unit 2 ACT 0109 worked example, 60 to 90 seconds
An Introduction and an Interruption
The idea
A sentence can open with an introductory element and also carry a nonessential interruption, and each needs its own commas. Step one: find the independent clause, its subject and its verb. Step two: put a comma after everything that comes before the subject. Step three: find any nonessential element inside the clause and set it off with a comma on each side.
In practice
Worked example: "When the lights came up Maria Santos who had led the orchestra for thirty years bowed." The independent clause is "Maria Santos bowed." A comma ends the introduction: "When the lights came up, Maria Santos." The clause about thirty years describes a person already named, so it is nonessential and takes a comma on each side: "When the lights came up, Maria Santos, who had led the orchestra for thirty years, bowed."
Where people slip
Each comma has a job: one ends the introduction, and two enclose the interruption. If the interruption has a comma on one side only, one of the pair has been lost.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Something wrong in this lesson? Flag it · Sources for ACT Preparation