Expanded Text Ads (ETAs) are a type of ad that is only able to contain 3 headlines and 2 descriptions.
Headlines are prominent snippets of copy containing up to 30 characters. Descriptions are beneath headlines in smaller font with up to 90 characters.
Since June 30, 2022, you are no longer able to create or edit ETAs within Google Ads. Instead, these types of ads have been replaced by Responsive Search Ads.