Day 190: Use that to start restrictive phrases.

Mistakes using that and which are probably the most common grammar problems we fix. This tip will deal with using that.

To understand how to use that, you need to understand restrictive phrases. It’s not too difficult, actually. Think of a category of things, such as cars at a repair shop or trees surrounding a house. A restrictive phrase focuses the reader’s attention on particular items in a category, such as one specific car or tree. Consider this sentence.

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“The car that is being repaired needs new brakes.”

Based on this sentence, multiple cars exist, but we want to identify one particular car: the car “that is being repaired.” In this way, we restrict, or limit, the reader’s attention from all the cars to one particular car. Here is another example.

“We removed the tree that was struck by lightning.”

Here, multiple trees exist. We want to restrict the reader’s attention from all the trees to one particular tree: the tree “that was struck by lightning.”

Here’s the simple rule for remembering this. If you need to tell the reader which one, use that, not which.