填入
is said
be done 被动语态有 there be done 的句式吗不是 there be done这里 is said to be 是插入语，去掉的话不影响句子。There is no life on the moon. 去掉to 之后，be动词还原为 is短语中的is said 表示被动.it is said 是常见的插入语，it is said to do 据说..