You just plain forgot!

They plain forgot that Marls a brain and could hear every word.

Because I was basing it on my car, and I plain forgot how much of Tannim's car is steel and Cold Iron, and all of it filled to the roof with spellwork.

"I have wanted to get to the big leagues for soooo long," he explained, "and wanted to get here so quick that I just plain forgot to pack 'em."

We plain forgot about old Ryan, didn't we?

But she's kept this place bright as a button, and I plain forgot that bottle and left it on the closet floor over there where any maid would find it.

- I had so much fun making love I plain forgot to come...

We're so used to dressing or not dressing according to what we need to do that I just plain forgot that I might not be behaving politely.

I plain forgot about it until now.