có hiệu lực v angličtině:

Do you think you have to be able to pass for a native speaker to be an effective spy?

I hear that studying in the morning is more effective. Studying one hour in the morning is as good as three hours at night.

OPP ineffective

I hope you're prepared to communicate under these conditions, because e-mail is most effective and convenient when different time zones are taken into consideration.

Everyone has the right to an effective remedy by the competent national tribunals for acts violating the fundamental rights granted him by the constitution or by law.

These quotations were effective in sending complex messages to his friends, because, in his day, people could quote from such authors with every expectation of being understood.

My father achieved that and more in four words, which made quoting Shakespeare as effective as any business adviser could wish.

The most effective means for the propagation of Esperanto is the fluent and elegant use of this language.

In order to bring about an effective agreement of wills, it is not sufficient to study other languages.

As of midnight tonight the contract becomes effective.

The art of modern warfare does not necessarily require soldiers to be armed to the teeth to be effective as combatants.

1. That picture would look more effective on a dark background. 2. The soldiers gained effective control of the town.

An effective writer is one who knows what sort of words should be employed in any specific context.

Out of the four policies that were suggested, I think the most effective one would be the "Improvement of Preventive Care and Health Promotion" policy.

Girls wearing mini-skirts, walking or sitting, are very effective eye-openers.