本句要先把特殊疑问词“why”去掉,根据句意可知意思是“昨天不让一场会议被举行来讨论它?”即“a meeting wasn't held to talk about it yesterday”一般疑问句“wasn'ta meeting held to ……?”特殊疑问句加上“why”就行了,句意为“为什么不让一场会议被举行来讨论它嫩?” 回答完毕,