Mixed Constructions

Mixed Constructions
A mixed construction is a sentence with incompatible elements that begins with one type of structure and shifts to another type of structure. In these sentences, the speaker sets out to say one thing and abruptly switches to something else resulting in confusion.
As a refresher, think of the sentence as a mathematical equation with the following structures:
Subject + predicate = sentence or Phrase + clause = logical connection
These will always make sense as distinct equations. However, one component of an equation is mixed with a component of another equation, the meaning becomes unclear. For example, consider the following revision:
Beginning in the fall of 1997, we began to charge students a trash tax, was the responsibility of student government. (Mixed Construction)
Beginning in the fall of 1997, we began to charge students a trash tax. The student government was responsible for this project. (Revision)

Understanding Mixed Sentence Structure

What if I told you that there's a type of sentence error that's exceedingly common, that's a major reason that teachers and professors deduct points from essays, and that is incredibly easy to spot and fix? So easy, in fact, that it doesn't require you to be able to define an independent clause, a coordinating conjunction, or a gerund? Sound too good to be true?
Just keep in mind: because you want your writing to be the best it can be, is why you should avoid mixed structure sentences.
Sounds a little funny, doesn't it? That's an example of a mixed structure sentence, which is a catch-all term for a sentence that starts off being structured one way but switches to a different structure halfway through. And like I said a moment ago, while this type of sentence error is fairly common, it's one of the very easiest sentence problems to identify and fix.
You may know from studying up on how to avoid run-on sentences, comma splices, and sentence fragments, for example, that it's important to understand and be able to identify various types of clauses and conjunctions to fix those errors. When it comes to mixed structure sentences, there's not an absolute rule that applies to fix each one.
Instead, mixed structure sentences can be quite varied, and the term applies to any sentence construction problem where the structure of the sentence changes halfway through. In this lesson, we'll review how good sentences can go off the rails and become mixed structure sentences as well as that aforementioned super easy, surefire way to catch and fix them.

How Mixed Sentence Structure Errors Occur

I get it. You don't have endless hours and hours to perfectly craft your writing assignments or a team of personal editors to comb through your papers before you turn them in. And, of course, standardized tests require that you write essay question responses quickly, which can leave the door wide open to grammatical mistakes.
Sometimes when you're writing, your mind might race as you try to get your sentences out, and the result is a jumble of words. Or, just the opposite, you might have a case of writer's block so terrible that you type out one. . . painful. . . word. . . at a time, and by the time you get to the period at the end of a sentence, you've long forgotten how that sentence started.
So, you might end up writing in a timed essay exam:
Although I'm a busy person, but I love to take time to study.
If you pay attention, you can see where the structure of this sentence implodes. The first half of the sentence is okay, and the structure makes sense up to a point: Although I'm a busy person,
And the second half, taken by itself, is okay, too: but I love to take time to study. But when we put them both together, it's not pretty.
Usually, fixing a mixed structure sentence takes just a bit of rearranging and double checking. We can solve this one by writing:
Although I'm a busy person, I love to take time to study.
Or you could write:
I'm a busy person, but I love to take time to study.
It's not exactly brain surgery, right? So, why do so many standardized exams feature questions requiring students to fix these types of errors? And how come so many English instructors spend sleepless nights grading stacks of papers with dozens of mixed structure sentence errors in them?

Catch and Fix Mixed Sentence Structure Errors

There's something that English teachers know, and that writers of standardized tests know, and that you'll now know, too: students hate proofreading their papers.
Students know they should go back through their papers to look for and correct mistakes, whether it's an essay with a deadline two weeks away, or a timed essay for a standardized test. But a lot of students don't do it, and others do it but kind of halfheartedly and not very well.
If you're guilty of being a bad proofreader of your own work, think about all of the points you could recoup with your grades by cleaning up mixed structure sentences that you might have dropped throughout your essay without realizing it. There are two surefire, easy ways to catch mixed sentence structure errors. The first is to read your finished essay aloud to yourself.