ACT Preparation / Unit 2 ACT 0106 short lesson, about 20 seconds
Which and That
Captions available
The idea
That introduces essential information and takes no commas. Which most often introduces nonessential information, set off by commas.
In practice
"The bike that won the race is for sale" picks out one bike. "Our bike, which won the race, is for sale" adds a detail.
Where people slip
A that-clause between commas is an error, because essential information never takes them.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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