In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.
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Question: A Horn clause with exactly one positive literal is a definite clause or a strict Horn clause ; a definite clause with no negative literals is sometimes called a unit clause , and a unit clause without variables is sometimes called a fact ; and a Horn clause without a positive literal is sometimes called a goal clause ( note that the empty clause consisting of no literals is a goal clause ) .

Answer: A Horn clause with exactly one positive literal is a definite clause ; a definite clause with no negative literals is sometimes called a “ fact ” ; and a Horn clause without a positive literal is sometimes called a goal clause .


Question: Since the list began , every serving President of the United States has been a Man or Person of the Year at least once with the exceptions of Calvin Coolidge ( in office at time of the first issue ) , Herbert Hoover ( the subsequent U.S. President ) , and Gerald Ford .

Answer: Since the list began , every serving President of the United States has been a Person of the Year at least once , except for Calvin Coolidge , Herbert Hoover , and Gerald Ford .


Question: During the American Civil War , the river , with few convenient fords and fewer bridges , provided a barrier and defensive line behind which movements of troops could be accomplished with little fear of attack from the river-side flank .

Answer:
During the American Civil War , the river , with few convenient fords and fewer bridges , provided a barrier and defensive line .