—Did you arrive here this morning?—Yes it was at nine o’clock we came here.A. whenB. befor

问题补充：

—Did you arrive here this morning?

—Yes,it was at nine o’clock we came here.

A. when

B. before

C. which

D. that

答案：

A. when

B. before

C. which

(答案→)D. that

解析：考查强调句型。本句被强调部分是at nine oclock。