The puzzle has given you six sets of pentominos printed with bigrams—letters and punctuation and capitalization. Standard pentomino puzzle-solving involves reassembling a full set of pentominos into a rectangle in any of the handful of 60-unit rectangles (6x10, 5x12, 4x15, 3x20), and an appropriate set of six frame shapes has been provided. You should notice some recognizable English words in the longer pentominos and realize that you have the pieces for constructing rectangle-shaped parodies of famous poems. The poems are constrained to have decent rhyme and meter (albeit not the same rhyme scheme or meter of the source material); word breaks (but not line breaks) occur at the grid edges. (In fact this property of word breaks is a constraint on concrete verse which the modestly-famous American poet George Starbuck invented, to both serious and comic effect, and which in parodic use he called SLABS—Standard Length and Breadth Sonnets—which is referred to, not that anyone is expected to catch it, in the flavortext.) Use the rhyme, meter, meaning, capitalization, and shapes to reconstruct the six poems.

Here are the correctly assembled poems:

Those should be recognizable as:

• “The Death of the Ball Turret Gunner” by Randall Jarrell
• “Dulce et Decorum Est” by Wilfred Owen
• “Ode on a Grecian Urn” by John Keats
• “We Real Cool” by Gwendolyn Brooks
• “The Owl and the Pussycat” by Edward Lear
• “The Road Not Taken” by Robert Frost

Now that you’ve assembled them, turn to the acrostic-indicator numbers and the numbered blanks. You will find yourself with the text:

• From EL: F and U
• From WO: I
• From RF: X
• From GB: V
• From JK: L and Z
• From RJ: N and Y

At this point it is necessary to have identified the poets of the source material. You’re being told to use “N and Y” from Randall Jarrell for example. What does that mean? Well, the pentomino shapes, originally defined by Solomon Golomb, have standard letter names:

(image credit R. A. Nonenmacher, CC BY-SA 4.0 on Wikipedia.)

The acrostic is telling you to select particular shapes from particular poets’ SLABS.

The partially-constrained grid didn’t have a unique fill when you didn’t know which nine pieces belonged there, but it does now, particularly because the piece orientations are fixed. Place the pentominos on the grid and you get:

You will see that the circled bigrams (top to bottom, left to right) are 't He s) ti NK In GR os :E, which minus punctuation is the answer THE STINKING ROSE.