All possible means _______. However, nothing can _______ him dying of lung cancer.
A.has tried; stop |
B.have tried; keep |
C.has been tried; prevent |
D.have been tried; stop |
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All possible means _______. However, nothing can _______ him dying of lung cancer.
A.has tried; stop |
B.have tried; keep |
C.has been tried; prevent |
D.have been tried; stop |