无效的英文怎么说

如果是要表达病能否治愈用cure,curable.比如：Is it curable?这能治愈好吗？Can this kind of disease be cured?这种病能治愈好吗？如果是表达自己已经治愈，痊愈了，一般说：I'm on my legs again.I'm well now.I'm completely over it.表达病情好转：I'm getting over it.I'm getting back on my feet.Things are looking up.I feel much better than before.invalid,null and void一般指的是法律上的无效，比如票，合同,契约等等.表达药品无效：It has not helped.