【答】这是侦探小说《血字的研究》“劳瑞斯顿花园街的惨案”上的一个句子，原文设置了一个对话情景。如果缺少上文，单独这个句子就不完整。我查阅了该句的来源出处，完整的对话是这样的：

Sherlock Holmes approached the body, and, kneeling down, examined it intently.

福尔摩斯走到尸体跟前，跪下来全神贯注地检查着。

"You are sure that there is no wound?" he asked, pointing to numerous gouts and splashes of blood which lay all round.

"你们肯定没有伤痕么？"他一面问，一面指着四周的血迹。

"Positive!" cried both detectives.

两个侦探异口同声回答说："确实没有。"

"Then, of course, this blood belongs to a second individual–presumably the murderer, if murder has been committed.

"那么，这些血迹一定是另一个人的喽，也许是凶手的。如果这是一件凶杀案的话，

It reminds me of the circumstances attendant on the death of Van Jansen, in Utrecht, in the year '34.

这就使我想起了一八三四年攸垂克特地方的范·坚森死时的情况。

Do you remember the case, Gregson?"

葛莱森，你还记得那个案件吗？"

"No, sir."

"不记得了，先生。"

"Read it up–you really should.

"你真应该把这个旧案重读一下。

There is nothing new under the sun. It has all been done before."

世界上本来就没有什么新鲜事，都是前人作过的。"

As he spoke, his nimble fingers were flying here, there, and everywhere,

他说话的时候，灵敏的手指这里摸摸，那里按按，

feeling, pressing, unbuttoning, examining, while his eyes wore the same far-away expression which I have already remarked upon.

一会儿又解开死人的衣扣检查一番；他的眼里又现出前面我谈到的那种茫然的神情。

So swiftly was the examination made, that one would hardly have guessed the minuteness with which it was conducted.

他检查得非常迅速，而且是出我意料地细致和认真。

Finally, he sniffed the dead man's lips, and then glanced at the soles of his patent leather boots.

最后，他嗅了嗅死者的嘴唇，又瞧了一眼死者皮靴子的靴底。

"He has not been moved at all?" he asked.

他问道："尸体一直没有动过么？"

"No more than was necessary for the purpose of our examination."

"除了进行我们必要的检查以外，再没有动过。"

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看红色部分，就知道省略了什么：

We did no more than was necessary for the purpose of our examination.

这个句子就很完整了，而且意思基本符合对话的情景。

字面意思是：对我们检查目的而言，我们做的仅仅是必须做的事情。

言外之意就是：除了进行我们必要的检查以外，再没有做过别的。

本句结构分析：

We （主语）did （谓语）no more （宾语）：主句

than （主语）was （系动词）necessary for the purpose of our examination （表语）：定语从句

than 是关系代词，指代no more；在定语从句中，than 作主语，was necessary for the purpose of our examination 是系表结构。

同意刘老师解答观点