Question

英语有个问题看不懂，请指教

Though it may be difficult to imagine from a later perspective, a strain of critical opinion in the
1920s predicted that sound film would be a technical novelty that would soon fade from sight, just as
had many previous attempts, dating well back before the First World War, to link images with
recorded sound. These critics were making a common assumption—that the technological
inadequacies of earlier efforts (poor synchronization, weak sound amplification, fragile sound
recordings) would invariably occur again. To be sure, their evaluation of the technical flaws in 1920s
sound experiments was not so far off the mark, yet they neglected to take into account important
new forces in the motion picture field that, in a sense, would not take no for an answer.

首先 我问的是 as just had many attemps ， 我想问的是 just as 的用法是什么？
为什么后面可以接上一个 had （过去分词形式）
just as 后面一般接什么？？？

然后 我 不懂得是 not so far off the mark 是什么意思？？
最后 that, in a sense, would not take no for an answer. 是什么意思 ？？
that 在这里引导的是什么从句，修饰前面句子的什么部分 ？？

Answer 1

尽管从后来者的观点看来有点难以理解,但是在1920年有一连串的批评预示着有声电影作为一种科技新产很快就会消失在人们的视野里,如同之前的多种尝试,这些把影像和录音结合的尝试可追溯到一战前.

just as 如同，好像。用在前后所提及的事物有类似之处。

这些批评家普遍认为- 早期工作的技术不足部分（同步效果，扩音，录音效果）一定会再次出现。当然，他们对有声电影中技术缺陷的评价也不是完全不准确。但是他们忘了考虑一点，那就是在某种意义上说电影领域的新势力是不会轻易放弃的。
off the mark 是个词组表示不相关，不准确。so是如此。far这里是程度副词。
no take no for an answer.不把“不”作为答案。引申意：不轻易放弃。

that我觉得是可有可无，没做什么成分。
take into account. 这里考虑的就是后面那些了。
后面那些完整的应该是：important new forces in the action movie field would no take no for an answer.

Answer 2

just as在这里是一个词组，正如...
此处的had用的是过去式，而不是过去分词，它与前面的would soon fade sight.时态是并列的。
just as后面可以接一个完整的句子。
在目前，是毫不相关的。
在某种程度上来说，那将会是一个很有前景的（领域）。
that在这里引导的是定语从句，（in a sense 是一个插入语）主要修饰的是前面的field.