20世纪六七十年代，为促进教育机会均等，英国工党政府将文法学校、技术中学和现代中学合并组建成新型中学。这种中学是（）。

A．完全中学 

B．统一中学 

C．综合中学 

D．文实中学

Not until he left his home _____ to know how important the family was for him.

A．did he begin

B．had he begun

C．that he began

D．he had begun