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Grammar Scientific Style Syntax Writing Tips

Dangling infinitives

The Miss Thistlebottoms of the world are always going on about dangling participles,1 but few usage experts mention dangling infinitives.2 What’s a dangling infinitive? It’s an infinitive, “to” + verb, that is not correctly attached to the agent (a noun or pronoun) that carries out the action specified by the verb. When a sentence starts with an infinitive phrase, the subject of the main clause should be the agent that carries out the action specified by the infinitive:

To prepare an NMR sample, we dissolved the crystals in CDCl3.

Here the pronoun “we” carries out the action specified by the infinitive “to prepare.” Infinitive constructions also work correctly when the subject is implied, as in an imperative sentence:

To prepare an NMR sample, [you] dissolve the crystals in CDCl3.

where the implied subject pronoun “you” is doing the preparing.

In scientific writing, however, we tend to use passive voice, especially in the experimental section of a paper; and the use of the passive eliminates the agent that is needed to carry out the action in the infinitive:

To prepare an NMR sample, the crystals were dissolved in CDCl3.

Now we have a problem: “crystals” is the subject of the main clause, but crystals do not prepare NMR samples.

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Grammar Scientific Style Syntax Writing Tips

Those and that: Implied antecedents

As a general rule, a pronoun should refer clearly to a single, explicitly stated antecedent and should agree with that antecedent in number. In my scientific editing, I encounter one particular violation of this rule in nearly every paper that crosses my desk. Here’s an example:

The ZnO peaks for the samples that were dried for 5 days are smaller than that for the sample that was dried immediately.

The singular demonstrative pronoun “that”  must have a singular antecedent, but the sentence contains no singular nouns. The author clearly meant “that” to refer to “ZnO peak,” which is implied but not explicitly stated. You might be inclined to leave this sentence unrevised, thinking that everyone will know what you mean. However, what about the following sentence?

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Grammar Scientific Style Syntax Writing Tips

A lost cause? Dangling “using”

With St. Jude and the late Robert Schoenfeld (former editor of the Australian Journal of Chemistry) at my side, I’m fighting a rearguard action against the ubiquitous dangling participle “using” in scientific English. I would be hard-pressed to find a single scientific paper that doesn’t contain a sentence like

Ab initio calculations were performed using the Gaussian program.

The metal content was determined using inductively coupled plasma–optical emission spectroscopy.

Using a PTFE fiber filter, the scrubbed off-gas was sampled.

Who or what is doing the “using” in these sentence? A participle like “using” must have a noun or pronoun to modify, and the only candidate nouns in these sentences—”calculations,” “content,” and “gas”—do not use programs, spectroscopy, or filters. Sentences like these certainly won’t get your paper rejected by your target journal, but if you want to “impress discerning readers”1 (and discerning referees), try not to leave “using” unattached to the noun that’s doing the using.