Ms. Angelou uses poeticlicense: the freedom to depart from the conventional rules of language when speaking or writing in order to create an effect.
never
Proper nouns
Unless they are proper nouns or begin a sentence, no.
No, you don't. The words "swine" and "influenza" are not proper nouns.
Yes, the words "History" and "Philosophy" should be capitalized when used as proper nouns or when referring to the academic disciplines.
In English writing, it is common to capitalize Latin words if they are used as proper nouns (e.g., names of specific entities) or titles. However, if Latin words are used in a general sense, they are typically not capitalized. It is important to follow the specific style guide or convention you are using for consistency.
Capitalize the first word in a sentence. Capitalize proper nouns, such as the names of people and places. Capitalize the pronoun "I." Capitalize the first word of a quote. Capitalize days of the week, months, and holidays. Capitalize the titles of books, movies, and songs. Capitalize the first, last, and important words in titles.
In most cases, the verb "did" is not capitalized in a title unless it is the first word or part of a proper noun. The standard practice is to capitalize the first word of the title, along with any proper nouns or words that are typically capitalized in a title.
Historians writing about the US Civil War capitalize both Rebel and Yankee. They do so as they are treated as proper nouns.
If you are writing something with a title, you would capitalize Happy Holiday Season in the title. If you are writing it in something other than a title, you would not capitalize it.
No. Unless it's at the begging of the title. In titles, you only capitalize important words (especially nouns). Other words you wouldn't capitalize in titles (unless they are at the beginning) are "or" and "that" (unless it's a noun)
In APA style, capitalize the first letter of the first word of the title, as well as the first letter of any proper nouns in the title. For journal articles, capitalize the first letter of the first word of the title, the first letter of the first word of the subtitle (if present), and any proper nouns in the title. All other words in the title should be in lowercase.