effective
effectual
efficient【导航词义:有效的】
effective adj. 有效的,起作用的
〔辨析〕指有效用的或能产生预期效果的。
〔例证〕
The government took effective measures to reduce the price.
政府采取了有效措施来降低物价。
The talks between both sides were effective in settling their disputes.
双方会谈有效地解决了彼此间的纠纷。
effectual adj. 〈正式〉有效果的,有实效的
〔辨析〕指产生希望或想要的结果的,只用于事物,如举措、药物、对策等。
〔例证〕
The government hasn't worked out the effectual measures to combat unemployment.
政府尚未找到应对失业的有效措施。
Quinine is an effectual preventive for malaria.
奎宁是预防疟疾的有效药物。
efficient adj. 有效率的,高效能的
〔辨析〕既可指人也可指事物,强调不浪费时间、金钱、能源等的。
〔例证〕
She is an efficient secretary.
她是一位得力的秘书。
The diesel engine is highly efficient.
这台柴油机效率很高。