Ao usar “To affect” o sentido é alterar ou influenciar, e um “effect” é algo que acontece a partir de uma causa.
When you affect something, it produces an effect.
Veja alguns exemplos de palavras usadas corretamente nestes sentidos:
The storm knocked down power lines, affecting several thousand people in rural communities. [CBC]
Gauging the disaster’s effect requires assessing economic activity that might be lost. [Wall Street Journal]
The regulator has estimated that its new rules will affect up to 11.3pc of borrowers. [Telegraph]
But the smell of freshly baked bread may have positive effects far beyond the obvious ones. [Independent Online]
Mas estas palavras tem outros sentidos menos usados que podem confundir. Por exemplo, Effect funciona como um verbo quando traz o sentido de “to bring about“. É a palavra correta em frases como effect change e effect solutions onde tem o significado de to bring about changee to bring about solutions. É possível imaginar onde a frase affect change faz sentido, mas ela significaria to have an effect on change em vez de to bring about change.
Os seguintes escritores, por exemplo, usam affect onde obviamente significam effect (to bring about):
His genuine desire to affect change was thwarted by a system which is stale and often ineffectual. [Independent]
This event shows that the press still has power, that written words can still affect change. [Indiana Statesman]
E os escritores abaixo usam o verbo effect corretamente:
Plenty of footballers do use their income to effect change, notably African players working in their home countries. [Independent (U.K.)]
Indeed, rushing to the Supreme Court is not always the wisest method for effecting legal change. [New York Times]