Question

that was the most worrying piece of news i would heard in a long time什么意思

Answer 1

那是我很久以来大概所听到的最揪心的消息。（原句有误，应该 是“... I would have heard ...")
关键词语：the most worrying piece of news最揪心（令人担心）的消息；I would have heard是定语从句，修饰the most worrying piece of news，I 前面省略了关系代词that; would是情态动词，表示推测, 可用于谈论过去，也可用于谈论现在(语气较will委婉, 比较不确定。), 意思是“大概、可能、应该等”；will / would +完成式（即have+过去分词）表示对过去可能已经发生的情况进行推测; in a long time 表示“很长时间、好久、很久、很久以来，有一段时间”。例如：
This car will / would hold six people. 这辆小汽车大概可以坐六个人。
He will be waiting downstairs now. 他现在应该在楼下等吧!
That would be in spring 1964. 那大概是1964年春天的事情。
You will / would have heard the news, I think? 我想，你已经听到那个新闻了吧?
I thought you would have finished it by now. 我想你现在可能已经做完了吧。
It's the best news I've heard in a long time. 这是我很久以来听到的最好消息。He hasn't seen you in a long time. 他很长时间没有见到你了。
I haven't had any contact with my family in a long time. 我和家里人已经很久没有联系了。
I haven't updated my bankbook in a long time. 我有一段时间没去打印我的银行存折了。

Answer 2

that was the most worrying piece of news i would heard in a long time
这是我会在很长一段时间里听到的最令人担心的消息，

Answer 3

that was the most worrying piece of news i would heard in a long time
这是最令人担心的消息我听到很长一段时间
这是最令人担心的消息，我会在很长一段时间里听到的
这是最令人担忧的一则新闻，我会听到很长一段时间
这是最令人担心的消息，我会在很长一段时间里听到的
这是我会在很长一段时间里听到的最令人担心的消息，

Answer 4

百度翻译为：

that was the most worrying piece of news i would heard in a long time
这是最令人担心的消息，我会在很长一段时间里听到

Answer 5

那将是我听到的最让人担心的消息，我今后很长一段时间里还会听到。
严格地说： that was the most worrying piece of news i would heard in a long time 愿句 中 would heard 为 would + heard (heard 是 hear 的 过去式或过去分词） ， 正确的应该是 would have heard 。

Answer 6

那是很长时间以来我听到的最令人担忧的消息。