revive old practices, customs, trends, etc
恢复旧做法、 再兴旧习俗、 重现某倾向
Repeating the same behavior will repeat the same result.
重复旧的做法，只会得到旧的结果。
They advocate old ideas, social systems and ethics, respecting Confucianism, restoring ancient ways, preserving the "quintessence" of Chinese culture and saving the nation by means of the classics.
他们提倡旧思想、旧制度、旧道德，主张尊孔、复古，保存“国粹”，读经救国。
Every summer, she climbed the Alps, startling the guides by singing loudly as she went.
“她复兴了旧画室，”他写到：“使旧灯复燃了，让哑音的旧钢琴重新响了起来。”
just a rework of an old speech.
仅仅是一个旧演说的重复
revenge for an insult,etc,esp(formerly)by means of duelling
（受辱后的）复仇,（尤指旧时）决斗
These are words which cannot Be staled By repetition.
这些话不会因重复使用而变得陈旧。
This new copy machine is more efficient than the old one.
这台新复印机比那台旧的效率高。
He can't return to work because he's had a relapse.
他不能回去工作，因为旧病复发了。
Take this medicine regularly, it will guard you against a return of illness.
按时服这种药，它会使你避免旧病复发。
The cold weather finds out my old wound.
严寒的天气使我旧病复发。
'Would he remember what took place in the relapse?'
“他能记得旧病复发时的情景吗？”
a return to normal working hours, old habits
正常工作时间、 旧习惯的恢复.
He stayed out the whole evening party
年复一年这城市依旧如故。
Take this medicine regularly; it will safeguard you against a return of the disease.
你要定时吃这种药以防旧病复发。
The old friendship was imperceptibly renewed.
旧日的友谊不知不觉地恢复了。
He spent two hours in going over the old lesson.
为复习旧课,他用了两个小时
The old German Empire ceased to exist in 1918.
到一九一八年，旧德意志帝国不复存在。