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Sentence Correction: Conditionals – Overview

The only way to detect a bacterial infection from Group A streptococcus is to perform a throat swab and culture and examine it under a microscope.

Incorrect.

This answer choice is stylistically flawed. The pronoun it is ambiguous because it agrees with several nouns that appeared before it - infection, streptococcus, swab, and culture.

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Well done!

This answer choice corrects the Pronoun ambiguity mistake in the original question by replacing it with the noun bacteria, which corresponds to the streptoccocus bacteria.

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Incorrect.

While this answer choice corrects the Pronoun mistake in the original question by replacing it with the noun bacteria, it is grammatically incorrect.

The construction A and B (perform and examining) requires that A and B belong to the same part of speech. In this case, A (perform) is a to V form, whereas B (examining) is a V+ing form.

What helps us identify this question as a Parallelism question as well as identify the mistake is the following Stop Sign:

         A and/or/but B

When you identify this structure, make sure it follows these rules:

1. A and B must be of the same part of speech.
2. A and B must be logically parallel.

Incorrect.

This answer choice is grammatically incorrect and stylistically flawed.

Why did you choose this answer choice?

Incorrect.

This answer choice makes incorrect use of the pronoun them.

Why did you choose this answer choice?

Grammatically speaking, them could refer to a throat swab and culture, but not logically.

From the point of view of logic, only the (singular) culture (of the streptococcus bacteria) is examined under a microscope to detect an infection, not the throat swab, which cannot have developed a culture before it was sent to the lab. Therefore the use of them in the corrected sentence is illogical.

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The plural pronoun them cannot refer to streptococcus, which is a singular noun.

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Unfortunately, this is not the case. The corrected sentence makes incorrect use of the conditional construction, because it does not describe a condition and result.

In addition, the use of the pronoun they in the corrected sentence is illogical as it can only refer to the plural noun throat swab and culture. However, logically speaking, only the (singular) culture (of the streptoccocus bacteria) is examined under a microscope to detect an infection, not the throat swab, which cannot have developed a culture before it was sent to the lab.

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While it is true that the verbs in the corrected sentence are grammatically parallel, using the passive form (are performed, are examined) creates redundancy. More importantly, however, the use of the conditional in the corrected sentence is grammatically incorrect, as the sentence does not describe a condition and result.

In addition, the use of the pronoun they in the corrected sentence is illogical as it can only refer to the plural noun throat swab and culture. However, logically speaking, only the (singular) culture (of the streptoccocus bacteria) is examined under a microscope to detect an infection, not the throat swab, which cannot have developed a culture before it was sent to the lab.

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Grammatically speaking, they could refer to a throat swab and culture, but not logically.

From the point of view of logic, only the (singular) culture (of the streptoccocus bacteria) is examined under a microscope to detect an infection, not the throat swab, which cannot have developed a culture before it was sent to the lab. Therefore the use of they in the corrected sentence is illogical.

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to perform a throat swab and culture and examine it
to perform a throat swab and culture and examine the bacteria
to perform a throat swab and culture and examining the bacteria
if a throat swab and bacterial culture are performed, and they are examined
after performing a throat swab and culture to examine them

I thought using the conditional if was a preferable way of expressing the meaning of the sentence.

It uses parallelism correctly: the verbs are performed, and are examined are grammatically parallel.

The plural pronoun they refers to the plural noun a throat swab and culture.

I thought that them referred to the plural noun a throat swab and culture.

I thought that them referred to streptococcus.