Question

Even though I’d hurt my leg, I＿＿＿＿＿＿ swim back to the river bank.

A．could

B．might

C．had to

D．was able to

Answer 1

D

can表示能力时可用be able to代替。但can只有一般时和过去时，be able to可用于各种时态。如果表示“过去有能力并成功地做成了某事"时，要用was/were able to，不用could。