Question

We ________ finish it ahead of time, though it was such a tough task．

1. A.
   could
2. B.
   would
3. C.
   were able to
4. D.
   ought to

Answer 1

C
解析：
考查情态动词。根据后文中though可知所填词表示“(经过努力后)能……”，所以应该用be able to, C项正确。