Identifying Sentence Errors

The following sentence contains either a single error or no error at all. If the sentence contains an error, select the one underlined part that must be changed to make the sentence correct. If the sentence contains no error, select choice E. 

Read the entire sentence, listening for errors.  Then quickly check each underlined portion of the sentence against the Big 8 Grammar Rules.

The Bear Gulch Limestone Formation in Montana is a sequence of bedded limestone layers up to 90 feet thick and approximately 8 miles acrossNo error

(A)  The word “in” is the correct preposition to indicate a location such as Montana.
(B)  The phrase “up to” is an idiomatically correct way to inform readers that the layers will not be more than 90 feet thick.
(C)  The word “and” is the correct conjunction to demonstrate the relationship between these two measurements.  There is no contrast between the two requiring a word such as “but,” and the two measurements do not depend on each other so they do not require a word such as “so.”
(D)  You are already given a number to describe the thickness of the layers, so you must have a way of telling what the second number measures.  The word “across” provides the needed information.
(E)  You found no errors.  Remember that you are not looking to revise the sentence; you are only looking for errors.

The correct answer is (E).

On, 44% of the responses were correct.

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