1. It was at this point that Mary lost it——lost control over her own body, lost the priceless political asset of her motherhood, soiled by her relationship with Bothwell.

结构剖析：这是倒装句式样，结构是：It+系动词+被强调部分+that+其余部分。这里是对时间状语进行强调——at the point。

其余部分主要是Mary，谓语lost，宾语是it。破折号后面的“lost control over her own body, lost the priceless political asset of her motherhood, soiled by her relationship with Bothwell”都是做it的同位语，补充说明这个“it”具体是什么东西。

同位语中，soiled by her relationship with Bothwell去分词短语做后置定语修饰同为语中的名词body和arrest。Body soiled by her relationship with Bothwell意思是：由于他们之间的关于而被玷污了的躯体。Arrest of her motherhood soiled by her relationship with Bothwell意思是：由于他们的关系而被玷污了的身为母亲身份的政治财产。

2. It need never have happened, had she been half the politician, Elizabeth, was.

结构剖析：这个句子是含有非真实条件虚拟句的一个复合句。

主句是： It need never have happened，从句是：had she been half the politician, Elizabeth, was。

从句和主句都使用了虚拟语气，主句的谓语结构式：need never have happened，这里使用情态动词+现在完成时，这个结构表示对过去的事情的虚拟，need have done意思是“本来有必要要做的事情而没有做”，而我们句子中使用的是其否定结构：need never have happened，意思是“不必要发生的事情发生了，可以避免发生的事情发生了”。

在从句中使用的倒桩结构。在条件虚拟句中，如果省略了if这个引导词，那么句子就要进行倒装。这类句子中有were, had, should等词时，把were, had或should置于句首。 例如：

例1：Were there no air or water, there would be no life in the world.

例2：Had you been more careful, such spelling mistakes might have been avoided.

我们的文中是将助动词had位于句首。再加上主语，位于，表语。此外，在这个省略if的条件状语从句中含有一个定语从句：the politician, Elizabeth, was，修饰前面的先行词half，由于关系代词在定语从句中做宾语，就省略了。在这个定语从句中，有一个同位语Elizabeth，它做politician的同位语，补充说明这个政治家的名字。

3. Then she'd have come down like a ton of bricks on Darnley's murderers, professing herself to be shocked at the crime, truly shocked, then presenting herself to the people of Scotland as a doubly victimised mother.

结构剖析：这是很有现在分词短语的复合句。

主句是：Then she'd have come down like a ton of bricks on Darnley's murderers。现在分词短语有2个，它们分别是： professing herself to be shocked at the crime, truly shocked和 presenting herself to the people of Scotland as a doubly victimised mother。这个两个现在分词短语都做伴随状况状语。