We can’t take part in the competition we get our student card.A. beforeB. ifC. WhileD. as

问题补充：

We can’t take part in the competition we get our student card.

A. before

B. if

C. While

D. as

答案：

(答案→)A. before

B. if

C. While

D. as

解析：词义辨析。A.before以前 B. If 如果 C. While即使 D. As 因为句意：拿到通行证我们才能比赛。根据句意选A