Question

I lived with my sister this summer and didn’t have to pay rent. So I _____ save most of my salary.

A．could

B．would

C．was able to

D．should

Answer 1

C

本題考查can和be able to的差別。
① can和be able to都可以表示有能力作某事，但be able to的主語必須是人或動物，而can 沒有這個限制，如：
He can swim. =" He" is able to swim.
The radio can be fixed in 30 minutes.（句中的can不能用be able to）
② 根據(jù)be動詞的變化而有各種時態(tài)的變化，而can只有過去時。
③ be able to表示克服困難或通過努力做成某事，其過去時可表示“設法做成”，相當于managed to do或succeeded in doing，而can表示本身具有能力做某事。如：
With the help of the firemen, they were able to leave the burning house.
本題是指通過節(jié)省房錢來攢錢，當然用be able to更合適，再如：
Although his leg was hurt, he was able to swim to the bank.