excerpt

Yes, this is possible.

The first step is to set up a child theme, so your changes won’t be overwritten when you update the theme. If you’re new to child themes, you can explore these guides:

http://codex.ww.wp.xz.cn/Child_Themes
https://www.smashingmagazine.com/2016/01/create-customize-wordpress-child-theme/
http://vimeo.com/39023468

Keeping your theme up-to-date is strongly recommended to ensure you get bug fixes, security updates, and updates to keep the theme compatible with WordPress core.

Once your child theme is set up, you could put a custom function in the child’s functions.php file to modify the default excerpt length:

Here’s an example from the Codex:

https://developer.ww.wp.xz.cn/reference/functions/the_excerpt/#div-comment-325

Let us know how it goes.

Sure! Thanks for your note.