time off for good behavior

基本解释

In PRISON you get time off for good behavior.
在监狱里，你可以好好表现，减少刑期。
bbs.pep.com.cn
IN PRISON: You get time off for good behavior.
在监狱：如果你表现好，你可以得到放假；
zhuoyang.spaces.live.com
In prison, you get time off for good behavior. At work, you get rewarded for good behavior with more work.
监狱里因为表现好他们给你减刑；工作时因为表现好老板奖给你更多的工作。

Al-Zaidi was initially sentenced to three years behind bars, but the term was later reduced, and he was granted additional time off for good behavior.

The report offers some practical solutions to the spending problem — sentence reductions, reinstating parole options, assigning increased time off for good behavior, etc.
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While aiding the law was part of his plea-bargain, testifying won't get him softer terms--only the proverbial "time off for good behavior" can do that.
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