Commas and Periods as Road Signs

Punctuation tells a reader when to pause and when to stop.

Punctuation marks work like road signs for your voice. A comma is a yield sign: slow down and pause briefly. A period is a stop sign: come to a full stop and let your voice drop, because the thought is finished. Ignoring these signs makes ideas crash into each other. Read this: 'Jamal packed apples, cheese, and crackers. Then he left for the hike.

' The commas separate the list, so you pause lightly after 'apples' and 'cheese'. At the period after 'crackers', your voice falls and you stop before starting the next sentence. Now imagine reading it with no pauses at all: 'apples cheese and crackers then he left' sounds like one long, confusing item. Watching for the signs keeps every idea in its own lane.

• 1A comma means pause briefly.
• 2A period means stop and let your voice drop.
• 3Commas in a list keep the items separate.