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Sentence Correction: Parts of Speech - Articles

Crohn's disease, not to be confused with ulcerative colitis, not only causes inflammation and ulcers but can create a number of abnormal openings or connections in the intestine.

Incorrect.

This answer choice is grammatically incorrect. Not only must be followed by but also.

[[snippet]]

Incorrect

This answer choice is grammatically incorrect and repeats the original Parallelism error. But also must be preceded by not only.

[[snippet]]

Incorrect

This answer choice is grammatically incorrect and repeats the original Parallelism error. The same part of speech that follows not only must follow but also. In this answer choice, not only is followed by a verb (causes) whereas but also is followed by a noun (a number of abnormal openings).

[[snippet]]

Incorrect

Although this answer choice corrects the original Parallelism error by complementing not only with but also, it is grammatically incorrect. The article amount of can describe non-count nouns only whereas the noun openings is a count noun.

What helps us identify this mistake is the following Stop Sign:

much, (a) little, less, the amount of

Very well done!

This answer choice corrects the original Parallelism error by complementing not only with but also.

not only causes inflammation and ulcers but can create a number
not only causes inflammation and ulcers but also a number
causes inflammation and ulcers but also can create a number
not only causes inflammation and ulcers but also creates an amount
not only causes ulcers and inflammation but also creates a number