I've got an MS Word document from a Chinese person. When I put comments in it, the font defaults to DengXian Regular, a Chinese font. How can one change that?

Currently, I change the font to Calibri for each comment box.

In the "Format" > "Font" menu, I see these two entries

Asian text font: DengXian (Body Asian) . . .
Latin text font: Times

when the text cursor is in the main text, but "Latin text font" becomes DengXian when the cursor is in a comment box.

As far as I can tell, no Chinese characters are used in the current document and so we can afford to disable Asian fonts altogether for this document, if such a thing is possible.

I use MS Office 2016 on macOS High Sierra.

Have a look at the font applied to the style called "Comment Text". This is the default style applied to Comments and is likely the reason your typeface is coming up that way.

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Andrew Lockton
Chrysalis Design, Melbourne Australia

Thank you for your help! That sounds exactly what I've been looking for, except I don't know where to find it. Before posting here, I looked into several places like Preferences but have failed to find a font setting for comments.

The list of styles you can see if often shortened by a setting that hides uncommon styles. To see all the styles in a document, first open the Styles Pane by clicking the tiny Dialog Launcher in the bottom right of the Home > Styles group on the ribbon (or press Alt-Ctrl-Shift-S)

Now, in the bottom of the Styles Pane, click on the third button (Manage Styles). Scroll through the list of styles to find the one called Comment Text (this is a lot easier if you sort the list alphabetically). Use the Modify button to check and change the font setting.

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Andrew Lockton
Chrysalis Design, Melbourne Australia