How does one turn off the annoying predictive words now appearing in messages on my MacBook Air?

I installed the latest update on my MacBook Air, and afterwards when I try and use messages, various words (they aren't actually predictive for me!) appear constantly as I write. This is beyond annoying. Soon we won't even have to think, right? These devices will read our minds and write our messages for us, perhaps even before we know what we want (or rather before they tell us what we are supposedly wanting).

Anyway, I digressed. I want to keep the spell check (!), but I just want my mind to decide what the next words are (not AI).