d.
6. Groaning of prisoners and clanking of chains were heard.
7. By the obtaining wisdom you will command esteem.
8. By reading of good books his style was improved.
9. The taking things by force is apt to make trouble.
10. A more careful guarding the prisoners would have prevented
this accident.

CHOICE OF RELATIVE PRONOUNS.[53]--_Who_ is now used only of persons;
_which_, of things; _that_, of either persons or things. As a rule,
euphony decides between _who_ or _which_ and _that_.

"_Who_ is used chiefly of persons (though also often of the higher
animals), _which_ almost only of animals and things (in old English also
of persons), and _that_ indifferently of either, except after a
preposition, where only _who_ [_whom_] or _which_ can stand. Some recent
authorities teach that only _that_ should be used when the relative clause
is limiting or defining: as, the man _that_ runs fastest wins the race;
but _who_ or _which_ when it is descriptive or co-ordinating: as, this
man, _who_ ran fastest, won the race; but, though present usage is perhaps
tending in the direction of such a distinction, it neither has been nor is
a rule of English speech, nor is it likely to become one, especially on
account of the impossibility of setting _that_ after a preposition; for to
turn all relative clauses into the form 'the house _that_ Jack lived _in_'
(instead of 'the house _in which_ Jack lived') would be intolerable. In
good punctuation the defining relative is distinguished (as in the
examples above) by never taking a comma before it, whether it be _who_ or
_which_ or _that_. Wherever _that_ could be properly used, but only there,
the relative may be, and very often is, omitted altogether; thus, the
house Jack built or lived in; the man he built it for."[54]

When the antecedent includes both persons and things,
_that_ is preferable to _who_ or _which_.

"When the antecedent is a neuter noun not personified, a writer should
prefer _of which_ to _whose_, unless euphony requires the latter."[55]

_What_, as a relative pronoun, is equivalent to "that which." It is never
used with an antecedent, since the antecedent is included in the meaning
of the word.

The word _as_ is a relative pronoun only after "such" or "same." After
"such" the proper relative is "as"; after "same" it is "as" or "that."
"_Same as_ usually expresses identity of kind, _same that_ absolute
identity, except in contracted sentences where _same as_ is alon