Remove Suggestions from MAIL application

The current version of MAIL on iPhones provides follow up suggestions as replies to incoming email. I find that it generally is not useful and just gets in the way. To turn it off go to the Settings app and then go to Apps and then scroll down to the MAIL app:

Scroll down the page and then turn off "Follow Up Suggestions" (the lower red arrow).

While you are there, consider also turning off "Summarize Message Previews" since it is often inaccurate and/or misleading.

On your Mac you can turn off suggestions in the Setting of the MAIL application: