Measure

Line breaks do not a poem make,
But line breaks there must be --
Three second lines make up their time,
And meaning makes each tree.

The pattern is the father, lines
That speak the poem's scales --
The rhythm is the mother, rhyme
A rule that rarely fails.

And syntax, grammar should be law --
Except when they should not.
Your poem ought to be a thought --
Unless it has a plot.

But if free verse is more your style,
You'd better demonstrate
That you know how to write in verse,
For that's the poet's gate.