1.economic/economical
两者均可表示“经济的”,其区别可简单地概括为:
①economic主要与“财政”有关
eg:The boy left school for economic reasons.
这男孩因经济原因而辍学。
②economical 主要与“节约”有关。
eg:To rent a house is more economical than to buy one.
租房比买房更经济。
2.ensure/insure
① insure:保险,给...投保
eg:After signing a contract with a professional baseball team,Jack decided to insure his pitching arm for $1 million.
和职业棒球队签约后,杰克决定为他投球的手臂投保100万美元。
② ensure:确保
eg:Please ensure (that) all lights are switched off.
请确保将所有灯都关掉。
③当表示"保证"的意思,两者通用,英国人爱用ensure,美国人爱用insure。
eg:Our precautions ensured/insured our safety.
预防措施保证了我们的安全。
3.electric/electrical
① electric:电的,用电的,带电的,指任何电动的或发电的装置,被修饰的物体本身可带电。
eg:electric light 电灯
eg:Please connect the two electric wires.
请将这两根电线接起来。
②electrical:电的,与电有关的,电气科学的,指与电有关的事物,被修饰的词本身不能带电。
eg:electrical engineer 电气工程师
eg:All the electrical work was done by my younger brother.
所有的电工活都由我弟弟来干。
eg:He buried himself in an electrical book.
他埋头读一本电学方面的书。