It is important to think over what you will do, to pursue your studies economically, and effectively.

Changes of leadership have a great effect on the international political economy.

It would be difficult to improve the device without an effective catalyst.

This sort of structure is called a double negative, but in effect it shows affirmation.

As yardsticks to measure the effectiveness of information retrieval there exist those called 'recall ratio' and 'precision ratio'.

She received the letter to the effect that he would soon be back.

He retires before the new pension scheme is due to come into effect.

When our class performed a play, I took charge of stage effects.