It covers a wide range of topics that relate to usage, including: plurals, nouns, verbs, punctuation, cases, parentheses, quotation marks, the use of foreign terms, and so on.

A Dictionary of Modern English Usage encourages a direct, vigorous writing style, and opposes artificiality, by advising against convoluted sentence construction and the use of archaisms.

Assisted in the research by Francis, who died in 1918 of tuberculosis contracted (1915–16) whilst serving with the British Expeditionary Force in the First World War (1914–1918), Henry dedicated the first edition of the Dictionary to his late brother:[10] I think of it as it should have been, with its prolixities docked, its dullnesses enlivened, its fads eliminated, its truths multiplied.

He had a nimbler wit, a better sense of proportion, and a more open mind, than his twelve-year-older partner; and it is a matter of regret that we had not, at a certain point, arranged our undertakings otherwise than we did. ...

This present book accordingly contains none of his actual writing; but, having been designed in consultation with him, it is the last fruit of a partnership that began in 1903 with our translation of Lucian.The first edition of A Dictionary of Modern English Usage was published in 1926, and then was reprinted with corrections in 1930, 1937, 1954, and in 2009, with an introduction and commentary by the linguist David Crystal.