OCG533, Fall 2001
Answers to assignment 2, Comma abuse
Here are ten sentences from the scientific literature. Comment on the right or wrong use of commas in each.
1. Original: On February 2, 1989, the DC-8 flew north from Norway
to Spitsbergen, then south to Iceland where it performed a series of maneuvers.
Comment: The trailing phrase where
it performed a series of maneuvers is incorrectly written as restrictive. In
order for this to be valid, there would have to be more than one Iceland. The
plane would have then flown to the Iceland where it maneuvered, not to any of
the other Icelands. Correct by inserting a comma before the final phrase.
Revised: On February 2, 1989,
the DC-8 flew north from Norway to Spitsbergen, then south to Iceland, where it
performed a series of maneuvers.
Further comment: The additional
comma makes the sentence choppy. Fix this by breaking it into two sentences.
Revision 2: On February 2, 1989,
the DC-8 flew north from Norway to Spitsbergen. It then continued south to
Iceland, where it performed a series of maneuvers.
Revision 3: On February 2, 1989,
the DC-8 flew north from Norway to Spitsbergen. From there it continued south to
Iceland, where it performed a series of maneuvers. [Smoother introduction to
the second sentence.]
2. Original: The atmosphere was not cold enough for ice clouds to
form, but 10 ppbv of nitric acid would have been supersaturated over a large
portion of the flight.
Comment: Here the comma is used
properly to separate two independent clauses connected by a coordinate
conjunction. No revision needed for this purpose. The sentence could be better
understood, however, by subordinating the first clause with although,
which seems to me to reflect the original meaning.
Revision: Although the
atmosphere was not cold enough for ice clouds to form, the 10 ppbv of nitric
acid would have been supersaturated over a large portion of the flight.
3. Original: Of the PSCs that were not water ice, about 35% were
solid, 44% were mixed phase, and 19% were liquid.
Comment: The comma is used
correctly to separate all members of the series. No revision needed.
4. Original: The ratios are remarkably constant, suggesting a
common source over the whole ocean or multiple sources with very similar
emission patterns.
Comment: The comma is used
correctly to separate a trailing participial phrase from the preceding clause
that it modifies. No revision needed.
5. Original: One strong feature emerging from macroalgal flux
measurements is that bromoform is invariably the dominant macroalgal by-product,
although the actual ratios of the bromoalkane release vary from one study to
another.
Comment: The comma is used
correctly to separate a contrasting element (“although the actual…”) from
the rest of the sentence. No revision needed. To my ear, however, even though
would be better than although. This is a minor point, however. [Note how
the contrasting element however is set off by commas.]
Revision: One strong feature
emerging from macroalgal flux measurements is that bromoform is invariably the
dominant macroalgal by-product, even though the actual ratios of the bromoalkane
release vary from one study to another.
Comment: The sentence could also be
written with the last two clauses reversed.
Revision 2: One strong feature
emerging from macroalgal flux measurements is that even though the actual ratios
of the bromoalkanes released vary from one study to another, bromoform is
invariably the dominant macroalgal by-product. [Emphasizes more the
dominance of bromoform relative to the previous revision, which emphasized the
differences in releases.]
6. Original: Previous bromoform source fluxes estimated from
observed remote marine atmospheric mixing ratios coupled with lifetime
calculations [Penkett et al., 1985] and from surface seawater
measurements combined with ocean-atmosphere exchange rates [Liss and Slater,
1974] were in the range 10–20 x 1011 g yr–1.
Comment: Probably wrong omission of
commas. Although we can’t look fully into the minds of the writers, they
probably intended to compare all previous measurements of fluxes of bromoform,
which happened to be obtained by the two methods stated, with those from their
new method. But they wrote something very different—they said all the previous
estimates of fluxes obtained with only those two techniques gave the
stated range of concentrations. They thereby left open the possibility that
there were other measurements with other techniques that they were choosing not
to consider. See the big difference? All previous measurements from any
technique versus all previous measurements with any technique. Assuming we have
looked into the writers’ minds properly, the sentence is most easily fixed by
setting off the phrase estimated…1974] by commas, thereby making it
nonrestrictive.
Revision: Previous bromoform
source fluxes, estimated from observed remote marine atmospheric mixing ratios
coupled with lifetime calculations [Penkett et al., 1985] and from
surface seawater measurements combined with ocean-atmosphere exchange rates [Liss
and Slater, 1974], were in the range 10–20 x 1011 g yr–1.
7. Original: In this study so far we have considered only removal
by HO and by photolysis.
Comment: The question is whether to
set off the introductory phrase In this study so far by a comma. Given
that it has two parts, In this study and so far, I think a comma
would better delineate the end of the phrase.
Revision: In this study so far,
we have considered only removal by HO and by photolysis.
Comment: I don’t like the sound
of the introductory phrase. I think the reason is that it is long followed by
short rather than the preferred short followed by long (everything else being
equal, of course). Note how much better it sounds with the parts reversed. I
don’t think this changes the meaning perceptibly, either.
Revision 2: So far in this
study, we have considered only removal by HO and by photolysis.
Further comment (not related to
commas): The sentence as written means that the writers have so far
considered only two topics, removal by HO and removal by photolysis. I will bet
that they really meant that they have so far considered only two mechanisms for
removal, by HO and by photolysis, which is not what they wrote. See the
difference? Only two topics versus only two mechanisms. The
position of only is critical! Fix by moving only to after removal.
Revision 3: So far in this
study, we have considered removal only by HO and by photolysis.
8. Original: The data are from three separate instruments, for
molecules with a variety of chemical characteristics, and are taken over a wide
geographic domain.
Comment: The question is whether
the commas properly connect the three members of the series. The answer is yes.
If you didn’t see that there was a series with three members of equal rank,
you are probably not alone. That is because the writers have not tried to give
the members parallel constructions to make it easier on the reader. Here is one
possible way to fix the problem by bringing out the inherent parallelisms.
Revision: The data are from
three separate instruments, from molecules with a variety of chemical
characteristics, and from a wide geographic domain.
Comment: If you don’t like all
these froms (note how the italics stop within the word), you can use with
instead.
Revision 2: The data were taken
with three separate instruments, with molecules with a variety of chemical
characteristics, and with a wide geographic domain.
Comment: Not so good. Try different
prepositions but keep the phrases short and as parallel as possible.
Revision 3: The data were taken
on three instruments, for molecules with a variety of chemical characteristics,
and over a wide geographic domain.
9. Original: The points corresponding to methyl ethyl ketone,
acetone, methanol, benzene, propane, ethane, acetylene, and CO (solid circles)
as well as toluene and hydroxyacetone are correlated and show an inverse
dependence of variability with lifetime.
Comment: The question is whether
the series and the phrase immediately after it are being handled properly. The
series up to the last element (and CO) has the proper number of commas.
The problem comes in the phrase that follows (as well as toluene and
hydroxyacetone), which is written restrictively but makes little sense when
viewed without the parentheses (…, and CO as well as toluene and
hydroxyacetone…). Better to write the phrase nonrestrictively.
Revision: The points
corresponding to methyl ethyl ketone, acetone, methanol, benzene, propane,
ethane, acetylene, and CO (solid circles), as well as toluene and hydroxyacetone,
are correlated and show an inverse dependence of variability with lifetime.
10. Original: The maximum bromide concentration occurred
approximately 5 m downgradient of the source trench with the advancing side of
the plume extending downgradient more than 100 m and the trailing side of the
plume extending upgradient only a few meters.
Comment: This sentence consists of
one relatively short independent clause (The maximum…source trench)
followed by a much longer trailing participial phrase (with the…meters.)
Since the phrase modifies the entire clause before it (it can’t modify just source
trench because it would then mean many source trenches and only one with the
advancing side…, which is nonsensical), it has be set off from the clause by a
comma.
Revision: The maximum bromide
concentration occurred approximately 5 m downgradient of the source trench, with
the advancing side of the plume extending downgradient more than 100 m and the
trailing side of the plume extending upgradient only a few meters.
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