The president could not effect a change in policy.总裁无力改变方针。As a political party they are trying to effect a change in the way that we think about our environment.作为一个政治党派，他们正在试图改变我们关于环境的观念。All our efforts availed us little in trying to effect a change.在企图实现一个变革中我们徒劳无功。