1. There are two mes in me.
2. I am a unique me.
3. I am me.
4. I am a me.
5. I am a ME.
6. I am ME.
7. I am Me.
(Are the expressions all grammatical? Can we use some in a poem? What is the difference?)
All are fine for use in poetry.
Please notice that in poetry, writers can take liberties with the language that would not be good in regular prose.
Here's an interesting interview with Karen Jo Shapiro:
http://www.npr.org/templates/story/story.php?storyId=103559357
For this poem, she too the rhythms and form of Joyce Kilmer's poem "Trees" and wrote her own words:
http://www.bartleby.com/104/119.html
All of the expressions you provided are grammatically correct. However, they differ in terms of capitalization and emphasis. Let's break them down:
1. There are two mes in me.
Here, "me" is written in lowercase, suggesting that it is being used as a general pronoun. It means that there are two different aspects or parts of oneself.
2. I am a unique me.
In this sentence, "me" is again written in lowercase, implying a general sense of self. It emphasizes individuality, suggesting that the speaker or subject is distinct and special.
3. I am me.
This sentence emphasizes the speaker's identity. By using "me" without any capitalization or additional emphasis, it highlights the simplicity and certainty of being oneself.
4. I am a me.
Similar to the previous sentence, this statement asserts the speaker's identity, but it does so in a more general way. By using the indefinite article "a," it implies that the speaker is one of many possible "me" versions.
5. I am a ME.
Here, "ME" is capitalized entirely, indicating emphasis. The capitalization adds intensity, suggesting that the speaker is emphasizing their identity or uniqueness in a stronger manner.
6. I am ME.
This expression is similar to the previous one, but instead of using the indefinite article "a," it leaves out any article altogether. By capitalizing "ME" and eliminating the article, it adds emphasis and boldness to the statement, reinforcing the speaker's identity.
7. I am Me.
This expression is similar to sentence 3, where the speaker asserts their identity by using "Me" without capitalization. However, with the initial capital "M," it adds a hint of significance or importance to the statement.
Regarding using these expressions in a poem, all of them can be employed creatively to convey different meanings and emotions. The choice would depend on the overall theme, tone, and intention of the poem. Words and phrases can be sources of inspiration for poems, so feel free to experiment with different combinations to add depth and individuality to your work.