问题补充：
The couple .I really don’t know why.
A. always quarrel
B. are always quarreling
C. have always quarreled
D. have always been quarreled
答案：
A. always quarrel
(答案→)B. are always quarreling
C. have always quarreled
D. have always been quarreled
解析：always同进行时态连用通常表示说话者赞扬、责备、厌恶等情绪。
