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Common Errors: sentence fragments
A sentence fragment is an incomplete structure that cannot stand on its own as a sentence:
When the Elephant hiccoughed.
Using three pairs of slippery thermal underwear.
To invoke the spirit of the compost pile.
In a desperate effort to avoid familial distractions.
Or else the cat might roll in the butter all afternoon.
Avoid using fragments like these as sentences. However, these dependent clauses are very useful in building sentences, to add information to a complete thought. For example: When the Elephant hiccoughed he blew a chartreuse bubble out his trunk.
Common Errors: the run-on sentence
Run-on sentences are independent sentences either linked with a comma (the comma splice), or simply run end to end (the fused sentence) and are regarded as improper:
Telephone tag has become a serious health hazard, it is particularly dangerous in a crowded office or with older heavier equipment.
Lawn mowers don't run well on catsup some varieties are highly corrosive.
Run-ons are easily corrected by creating two separate sentences, making one a dependent clause, or by linking the phrases with a semicolon, or a conjunction.
Telephone tag has become a serious health hazard, particularly in a crowded office or with older, heavier equipment.
Telephone tag has become a serious health hazard; it is particularly dangerous in a crowded office or with older, heavier equipment.
Telephone tag has become a serious health hazard and is particularly dangerous in a crowded office or with older, heavier equipment.
Lawn mowers don't run well on catsup; some varieties are highly corrosive.
Lawn mowers don't run well on catsup as some varieties are highly corrosive.
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Excerpted with permission from
SAT Practice: The New Verbal Section.