Whether we should say “One ought to know one’s own mind,” or “One ought to know his own mind,” is a question that the critics have earnestly discussed, but have never settled, except as each settles it for himself. The masculine pronoun is often used with an antecedent whose gender is not known. There can, therefore, be no objection to the use of his on the question of gender. As a matter of euphony, his is preferable to one’s. Both have the sanction of good usage.
None
Although literally signifying no one, the word none may be used with a plural verb, having the force of a collective noun.
“None but the brave deserves the fair.”— Dryden.
“None knew thee but to love thee,
None named thee but to praise.”—Halleck.
“I look for ghosts; but none will force
Their way to me.”—Wordsworth.
“Of all the girls that e’er were seen,
There’s none so fine as Nelly.”—Swift.
All, Whole
The word all is often incorrectly used for the whole.
“The river rose and spread over all the valley.” This should be “over the whole valley.”
“The day being stormy, the members of Class A were all the children at school to-day.” Correct by saying “were the only children at school to-day.”
Perpetually is not synonymous with continually. Perpetually means never-ceasing. That which is done continually may be subject to interruptions.