Misplaced modifiers are words or phrases that alter the meaning of a sentence. When we say that a modifier has been misplaced, we mean that the word or phrase that the modifier is altering has been changed. We are dealing with sentence ambiguity when we have sentences with misplaced modifiers. A great example of a misplaced modifier comes from a quote by Groucho Marx. He says "One morning I shot an elephant in my pajamas. How he got into my pajamas, I'll never know" (Bartlett).
When you're done writing your paper, check for any sentence level ambiguity. One way of doing this is to start from the end of your paper and focus on one sentence at a time, starting with the very last one. This takes the sentence out of the larger context, so that you can focus on the clarity of the sentence.
Another example of a misplaced modifier is: "I like to listen to music doing my homework."
Is music doing your homework, or do you like to listen to music while you are doing your homework? One simple word can change the meaning of your sentence.
Another method of ridding your sentences of misplaced modifiers is to have somebody else look over your paper. Other people may catch ambiguity that you missed!
Bartlett, John. Kaplan, Justin, Ed. Bartlett’s Familiar Quotations, 16th Edition. Boston: Little, Brown & Company, 1992, p 693.