Let's start working at once.; Act without delay.

说干就干。

《新英汉大辞典》

It's usually best to wait, but in the present case I'd advise you to act without delay.

通常情况下最好是等待，但眼下的情况我倒是建议你立即采取行动。

youdao

We have to act now, without any delay.

我们必须现在就采取行动，不能有任何迟缓。

youdao

He urged the "rational" traditional leadership of the Brotherhood to act without delay to curb this tendency.

ECONOMIST: Is the Muslim Brotherhood turning its back on politics?

Importantly, if the employee is underperforming, document performance, follow appropriate standards within the organization and act without delay.

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But I also want to urge all members of Congress to act without delay in the coming week to resolve their differences and pass this plan.

WHITEHOUSE: Presidential Press Conference