Grammatical structure

Once you head into a sentence, your choices are limited by the range of grammatical patterns in English. You cannot begin with one grammatical plan and switch without warning to another.

Heading: Mixed. Incorrect example sentence: For most drivers who have a blood alcohol level of .05 percent double their risk of causing an accident.

The writer began with a long prepositional phrase that was destined to be a modifier but then tried to press it into service as the subject of the sentence. A prepositional phrase cannot serve as the subject of a sentence. If the sentence is to begin with the prepositional phrase, the writer must finish the sentence with a subject and a verb.

Heading: Revision 1. Example sentence: For most drivers who have a blood alcohol level of .05 percent, the risk of causing an accident is doubled.

The writer who wishes to stay with the original verb (double) can head into the sentence another way.

Heading: Revision 2. Example sentence: Most drivers who have a blood alcohol level of .05 percent double their risk of causing an accident.

Example sentence with editing. Original sentence: When an employee is promoted without warning can be exciting or alarming. Revised sentence: Being promoted without warning can be exciting or alarming.

The adverb clause When an employee is promoted without warning cannot serve as the subject of the sentence. The revision replaces the adverb clause with a gerund phrase, a word group that can function as the subject.

Example sentence with editing. Original sentence: Although the United States is one of the wealthiest nations in the world, but more than 12 million of our children live in poverty. Revised sentence: Although the United States is one of the wealthiest nations in the world, more than 12 million of our children live in poverty.

The Although clause is subordinate, so it cannot be linked to an independent clause with the coordinating conjunction but.

Occasionally a mixed construction is so tangled that it defies grammatical analysis. When this happens, back away from the sentence, rethink what you want to say, and then say it again as clearly as you can.

Heading: Mixed. Incorrect example sentence: In the whole-word method children learn to recognize entire words rather than by the phonics method in which they learn to sound out letters and groups of letters.

Heading: Revised. Example sentence: The whole-word method teaches children to recognize entire words; the phonics method teaches them to sound out letters and groups of letters.

ESL: although, because

ESL: Double subjects and other repetition

Exercise: Mixed constructions 1

Exercise: Mixed constructions 2

Exercise: Mixed constructions 3

Exercise: Mixed constructions 4