I have read that it takes 21 days for a habit to take effect, which is why I mention a 30 day period of testing anything new.

我曾经读到过，要培养一个习惯，需要21天，这也就是为什么我提出用30天的时间来尝试新的改变。

youdao

These men undergo a long period of testing and training.

这些人要经受长期的测试和训练。

youdao

A small community of design firms and regulators in North Carolina is currently testing the model, and after this trial period, it will be available free to the public on Bill Hunt's university faculty webpage.

VOA: standard.2010.08.04

Following a period of testing and development, the NPSA plans to roll-out the system across the NHS in England and Wales from 2003.

BBC: Patients 'at risk' from drug errors

The Rangers pressed hard for the winner at the start of the extra period with Callahan testing Holtby.

WSJ: Backstrom, Ovechkin lead Caps to 3-2 SO win

The application period closes in January, but after the period closes, there is an extensive period of review, interviews, medical testing, and other things.

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