— Were you worried about him last night?　　　　— Yes. It was .A. until he returned that I wen

问题补充：

— Were you worried about him last night?

— Yes. It was .

A. until he returned that I went to bed

B. until be returned that l slept well

C. not until he returned that I went to bed

D. not until did he return that I went to sleep

答案：

A. until he returned that I went to bed

B. until be returned that l slept well

(答案→)C. not until he returned that I went to bed

D. not until did he return that I went to sleep

解析：此处强调句型，强调是until从句，如复原应为I didn go to bed until he returned.这个句型变为强调句型应注意，主句中的not在强调句中移至until之前。