Time travel's tricky;
Try to talk tenses, then trip.
Today? Tomorrow?
You think you were first
But I will be before you
In half an hour.
English grammar has
Past, future and present tense
This does not suffice.
When Unstuck in Time
One must sort out in advance
What tenses to use.
We haven't yet been
Entering from tomorrow
But we soon yethave.
I will have written
This haiku in the future
Already did that.
