It is vital that the work _______ in time.
B
这里主语从句中应该用虚拟语气，从句谓语用should+动词原形的形式，should可以省略。句意：及时完成这项工作是极其重要的。
Sincewehaveafocusedsubject，weshouldnottalk________.
Thevehiclewastravelingatspeeds________90milesperhour.
Thestudentsarerequiredto________themainideasofthearticleintheirownwords.