Locally change the font family [closed]

This is not really a WordPress question but I’ll answer it anyway. The first thing you need to know is CSS is your friend. You’ll want to do something like this:

In style.css
.serif-class {font-family: "Times", "Times New Roman", serif;}

Then using the html view inside of your post:
<span class="serif-class"> This is an important sentence </span>

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