These poems are radically different in terms of their structure and form. Whyte's poem is written in blank verse, meaning that it has no regular rhyme scheme or meter. The lines are differing lengths; some are even single words ("tested"). The poet uses line breaks for emphasis; the meaning of the poem is shaped by the poet's decision to isolate small groups of words or phrases as their own lines. This draws the eye—note especially examples like

and I
bewildered by

where, by introducing two very short lines on their own, with an unexpected rhyme, the poet is able to create a sort of caesura or pause in the flow of what he is saying. The power of this poem is in its sheer unexpectedness, forcing the reader to interrogate the language used and the question of what poetry really is.

By contrast, the power of "Three Limericks" is very predictable. Unlike Whyte's poem, here we see a very traditional poetic form used: the limerick. In accordance with traditional limericks, each limerick in this group follows an AABBA rhyme scheme; even the meter is constrained to fit within strict guidelines. As such, traditional meter and form is used to highlight the variation that can be achieved even within traditional parameters, while Whyte deliberately flouts traditions in order to cast a different light on them.

John Whyte's "I've Always Lived Across the Street" is a great, fun poem to read.  A reader would need to read it for its content rather than its rhythm and meter.  The reason for that is the poem is written in free verse.  That means there is no rhyme scheme or regular meter.  

Let's look at the rhyme scheme.  If you were to chart out the first 10 lines of the poem, the rhyme scheme would look like this: ABCDEFFGBH.  As you can see there is no regular rhyme to the poem.  There are two rhymes in those 10 lines, but Whyte makes no attempt to have any sort of regular, reoccurring rhyme. If we look at the meter and check the syllable count, the first 10 lines look like this: 4444546345.  The first four lines indicate the possibility of dimeter, but lines like "the disappointment did not dissuade me" clearly show Whyte is not making an attempt to stick with four syllables.  

The other structure element would be stanza organization. The poem is one big long stanza.  

When I was younger, I never enjoyed poems like that. I didn't understand how they could be called poems if they didn't have rhyme, rhythm and meter, or stanzas.  I felt it was more prose than poetry.  Whyte's poem is a poem, though, because it condenses so much thought and emotion into so few words. 

"Three Limericks" by John Robert is the complete opposite of Whyte's poem.  A limerick is a very tight form of poetry.  It has rules about a specific rhyme scheme (AABBA) and meter.  The meter is not as tight as a sonnet, which is 10 syllables per line.  Colombo's limericks show the standard 5-line stanza with lines 1, 2, and 5 rhyming.  Lines 3 and 4 also rhyme with each other.  Lines 1, 2, and 5 are between 8-12 syllables, which is very loose.  But lines 3 and 4 are always fewer syllables than the other lines.  Colombo also sticks closely to anapests as indicated by lines like "in the gunpowder jar."  

Compare and contrast rhythm, form, and structural devices in "I've Always Lived Across the Street" and "Three Limericks."

John Whyte's "I've Always Lived Across the Street" is written in free verse.  That means it has no set rhythm and meter.  Some lines have 4 syllables, some have 6, some have 5, and some have 12.  Other syllable counts exist throughout the poem as well.  Since there is no regular repeating syllable count, even if a poetic foot were used, there still wouldn't be a regular meter.  The poem also does not have a rhyme scheme. Its form is a single stanza.  The poem contains hyperbole in the line "hot enough to fry an egg on the sidewalk." It also contains a great pun on the names "Somebody" and "nobody." 

Colombo's limericks are very different. A limerick is a form of poetry that is contained within a 5 line stanza.  Lines 1,2, and 5 must rhyme and be in the same poetic rhythm and meter.  Lines 3 and 4 rhyme with each other and must be a different meter than the other lines.  They also must be a shorter meter. Colombo's limerick's follow those rules.  His lines 1, 2, and 5 are not always the same syllable count, but they are always at least one extra foot longer than lines 3 and 4. For example:

There was a young man of South Bay, (8 syllables)                      
Making fireworks one summer day,  (9 syllables)             
                He dropped his cigar   (5 syllables)                      
                In the gunpowder jar… (6 syllables)
There was a young man from South Bay. (8 syllables)

As you can see, the syllable counts don't stay exact (like a perfect limerick would), but the basic limerick form is definitely intact. That limerick also contains a great play on words.  Lines 1 and 5 are identical, but line 5's emphasis on "was" indicates that the man from South Bay is dead.  The reader wouldn't have assumed that based on the first line.  This is typical of most limericks.  A humorous ending that often makes use of a pun.