There's a good deal of slack to be taken up before they have reached full productive capacity.

他们还得好好整顿才能达到最高的生产能力。

youdao

It's one thing to have a job, but if there's slack demand for what you do, how productive can you be?

BBC: Picking up the slack

This is going to put pressure on employers to pick up the slack if they want to retain a focused, productive workforce.

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