The health official said ______ 12 suspected cases of influenza A (H1N1) were tested negative and ______, so far, this city has reported no case of the virus.
---Is it good to look up every new word when I come across it in reading?
---No. You ______because you are likely to guess the meaning from the context.
A. can’tB. mustn’tC. don’t have to C. ought not to