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

答案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。
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