Edwin Abbott

Use "every" or "a single

not ought to be separated from intend

"You say you don't want both butter and honey—you want butter or honey; I, on the contrary, do not want butter or honey—I want them both."

"I do not see them both—I see only one of them."

"that" depends upon "so" or "statement."

"Certain" is often used for "some,"

Writing clearly does not imply thinking clearly

Do not use "and which" for "which."