Answer:
nor MARS his SWORD nor WAR'S quick FIRE shall BURN.
Explanation:
Accent marks or diacritical marks are those marks that are put either above or below a word to bring difference in the pronunciation, stress, or even meaning.
A breve is a mark that is put on an unstressed word. Breve symbolises a short or unstressed vowel in a word.
The given sentence is written in an iambic pentameter style which means that that are five meters with an unstressed syllable followed by a stressed syllable.
So, to depict an accent mark I have written the word in capital and breve in small letters.
nor MARS his SWORD nor WAR's quick FIRE shall BURN.
