We must apply what we have learned to our daily work because in no case from practice.
A. should theory separate
B. theory should be separated
C. theory should separate
D. should theory be separated
网友回答
A. should theory separate
B. theory should be separated
C. theory should separate
(答案→)D. should theory be separated
解析：句意：我们必须把我们学到的应用到实际生活中去，因为在任何情况下理论都不应该脱离实际。这里是apply sth to sth把……应用到……，in no case在从句中的句首，所以应该用倒装，又因为theory与separate之间是被动关系，故选D。