It's unwise of you to consider his wild behaviour as no more than a kid's game. It may gradually develop into a bad habit.

你把他这种疯狂行为视为不过是小孩子嬉戏，这是不明智的。这种行为可能会逐渐助长成为坏习惯。

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Daily drinking, for example after a hard day's work, can develop into a bad habit over time.

每日饮酒，例如在辛苦工作一天后饮酒，会逐渐养成一种坏习惯。

youdao

It's easier to develop a good habit than it is to break a bad habit.

培养一个好习惯要比改掉一个坏习惯来的容易。

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From a risk management standpoint, giving up over a 10% gain is a bad habit to develop if you want to make money over the long haul.

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