– Sir we have failed to work out this problem. What is exactly the right way?--- Look. On

问题补充：

– Sir, we have failed to work out this problem. What is exactly the right way?

--- Look. Only in this way , but you boys a wrong way.

A. you can work it out; take

B. you can work out it; take

C. can you work it out; take

D. can you work it out; took

答案：

A. you can work it out; take

B. you can work out it; take

C. can you work it out; take

(答案→)D. can you work it out; took

解析：第一空考查倒装句，only + 状语放在句首，使用部分倒装，可排除A和B两项，第二空考查时态，根据语境用错方法的动作在过去，所以用一般过去式，故选D。