为什么雕刻玻璃要用HF 用NAOH为什么不行

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• A good many proposals were raised by the delegates,as was to be expected.这里为什么要用to 不用to be行不行啊?哈哈！我认为两个人的综合起来就对了！即：这里的as was to be expected 是个定语从句，as是引导词，在定语从句中作主语，指代前面整个句子A good many proposals were raised by the delegates；同时was to be 表示过去将来时的被动语态；而as was expected.只表示被动，表示已发生的事实，这里是过去将来时，所以用to be，
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