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.

Q: The boundaries between perennial , intermittent , and ephemeral channels are not defined , and subject to a variety of identification methods adopted by local governments , academics , and others with a need to classify stream-flow permanence .

A: The differences between perennial , intermittent , and ephemeral streams are not exact and can change if different measures are used by different groups .
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Q: The UN Declaration on the Elimination of Violence Against Women states , " violence against women is a manifestation of historically unequal power relations between men and women " and " violence against women is one of the crucial social mechanisms by which women are forced into a subordinate position compared with men . "

A: The United Nations ' Declaration on the Elimination of Violence against Women says : " violence against women is a manifestation of historically unequal power of relations between men and women . "
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Q: He returned to France to be air navigation director of Direction de la navigation ae rienne now called Direction des Services de la navigation ae rienne until 1993 .

A:
He returned to France to be an air navigation director until 1993 .
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