She felt it was incumbent on herself to act immediately.

她感到立即采取行动是她义不容辞的责任。

《柯林斯英汉双解大词典》

We have to act immediately. We have to fight for it.

我们必须立即采取行动，我们必须为之战斗。

youdao

Management should act immediately if these things are happening in a company.

如果这种情况在公司里发生，管理层应该立即干预。

youdao

The New York demonstrators, who included activists from Latino,Caribbean, and Asian communities in New York as well as local clergy members, called on President Obama to act immediately to stop Arizona's law from being implemented.

VOA: standard.2010.04.28

Wilson wasted no time. He immediately called a special session of Congress to act on Democratic campaign promises to reduce import taxes,or tariffs.

VOA: special.2010.09.23

The BOP should act immediately to end these and other unnecessary and wasteful policies.

FORBES: Sequester As Opportunity? Simple Ways To Cut Prison Spending, Maybe Avoid Furloughs

President Bush today urged Republican members of Congress to act immediately on the new economic stimulus package.

NPR: Bush Urges House Republicans to OK Stimulus Plan

Gettelfinger again Thursday called on Congress and the Bush administration to act immediately.

FORBES: Magazine Article