Question

Not until _____,_______the diffiult problem.

1. A.
   did he return;we settled
2. B.
   he returned;we settled
3. C.
   did he return,did we settle
4. D.
   he returned;did we settle.

Answer 1

D
本题考查倒装。Not until位于句首时，主句要用部分倒装，但until后的从句不倒装。