Its use as a virtual equivalent of although is allowable in sentences where this leads to no ambiguity or absurdity.
While I admire his energy, I wish it were employed in a better cause.
This is entirely correct, as shown by the paraphrase,
I admire his energy; at the same time I wish it were employed in a better cause.
Compare:
While the temperature reaches 90 or 95 degrees in the daytime, the nights are often chilly. Although the temperature reaches 90 or 95 degrees in the daytime, the nights are often chilly.
The paraphrase,
The temperature reaches 90 or 95 degrees in the daytime; at the same time the nights are often chilly,
shows why the use of while is incorrect.
In general, the writer will do well to use while only with strict literalness, in the sense of during the time that.
Whom. Often incorrectly used for who before he said or similar expressions, when it is really the subject of a following verb.
| His brother, whom he said would send him the money | His brother, who he said would send him the money |
|---|---|
| The man whom he thought was his friend | The man who (that) he thought was his friend (whom he thought his friend) |
Worth while. Overworked as a term of vague approval and (with not) of disapproval. Strictly applicable only to actions: “Is it worth while to telegraph?”
His books are not worth while. His books are not worth reading (are not worth one's while to read; do not repay reading; are worthless).
The use of worth while before a noun (“a worth while story”) is indefensible.
Would. A conditional statement in the first person requires should, not would.
I should not have succeeded without his help.
The equivalent of shall in indirect quotation after a verb in the past tense is should, not would.
He predicted that before long we should have a great surprise.
To express habitual or repeated action, the past tense, without would, is usually sufficient, and from its brevity, more emphatic.
Once a year he would visit the old mansion. Once a year he visited the old mansion.