下列痤疮愈后不留瘢痕的是（）
A.聚合性痤疮
B.结节性痤疮
C.囊肿性痤疮
D.坏死性痤疮
E.以上都不是
参考答案：E
They had no sooner arrived at the bus station than the bus .
A．had left
B．will leave
C．left
D．is leaving
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