I failed in the spoken examination last term and only then _______ the importance of practicing speaking English.

A．I had realized

B．had I realized

C．I did realize

D．did I realize

构音组合训练、句子组合训练属于（）。

A.发音训练

B.语音训练

C.构音器官训练

D.语言节奏训练

E.言语代偿方法训练