What are some ways to compare the language features in ''Ozymandias'' and ''My Last Duchess''?

This is a great question; these are two of my favourite poems! Let's look at several ways you can compare these two poems.

We can start by looking at the structure of these two poems. Both poems rhyme and are written in iambic pentameter. Iambic pentameter means that each line is composed of an unstressed syllable followed by a stressed syllable, five times. "My Last Duchess" follows iambic pentameter more strictly than "Ozymandias" does. The rhyme scheme is different, too; "My Last Duchess" follows the pattern AABBCC (etc) while "Ozymandias" follows the pattern ABABCDCD (etc.) In addition, the rhyme scheme in "Ozymandias" is looser, and Shelley used a lot of near-rhymes in this poem, such as stone-frown. These two words do not exactly rhyme, but they have similar sounds, so they are considered near-rhymes.

Both poems are written in first person narrative. The first line of "My Last Duchess" is, "That’s my last Duchess painted on the wall," and the first line of "Ozymandias" is, "I met a traveller from an antique land." The use of first-person pronouns my and I make it seem as though the narrator is talking directly to the audience, and the effect is that the audience is drawn in and enraptured.

Both poems use quoted speech. Line two of "Ozymandias" reads, "Who said—“Two vast and trunkless legs of stone," and then the remainder of the poem is in quotation marks as the words said by the "traveller" mentioned in line one. "My Last Duchess" lines 15 to 19 contain two instances of quoted speech:

                               ...perhaps

Fra Pandolf chanced to say, “Her mantle laps

Over my lady’s wrist too much,” or “Paint

Must never hope to reproduce the faint

Half-flush that dies along her throat.”

The use of quoted or recorded speech in these two poems make the audience feel as if they are listening to the narrator tell a story. It makes the story told in the poem more immediate and makes the audience feel like they are there in the room with the narrator.

     Both poems also use alliteration. Alliteration is a literary device in which a number of words with the same consonant beginning sound are used close together. The use of alliteration makes a poem more enjoyable to read, and more lyrical, and can also add to the mood or aural imagery in the poem. The last two lines of "Ozymandias" read: "...boundless and bare / The lone and level sands stretch far away.” These lines have two examples of alliteration. The repetition of the "b" sound in "boundless and bare" and the repetition of the "l" sound in "lone and level" give the poem a pleasing sound. In "My Last Duchess," Shelly uses lots of alliteration. One example is in line 29: "She rode with round the terrace." The "r" sound is repeated in "rode," "round," and again in the middle of "terrace." This alliteration again makes the poem lyrical and lovely to listen to.

     "Ozymandias" also uses a special kind of alliteration called sibilance. Sibilance is the repetition of the 's' sound. When you read "Ozymandias" aloud, you can hear the 's' sound repeated in almost every line. This creates aural imagery: it is as if you are hearing the desert sand blowing in the wind, and the anger in the voice of the tyrant Ozymandias as he spits out his words. 

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