Urgent
Part of speech: adjective
Definition: Requiring immediate attention.
Example sentence: The cancer that demands our urgent attention is corruption and poverty.
Imperative
Part of speech: noun
Definition: The grammatical mood expressing an order (see jussive). In English, the imperative form of a verb is the same as that of the bare infinitive.A verb in imperative mood.An essential action, a must: something which is imperative.
Part of speech: adjective
Definition: essentialHaving a semantics that incorporates mutable variables.
Example sentence: The most tragic paradox of our time is to be found in the failure of nation-states to recognize the imperatives of internationalism.