They also seemed of very doubtful value.是什么意思？

They also seemed of very doubtful value.

它们好像也没有多大价值。

they

pron. 他/她/它们，人们，大家，政府，当局，她们；

例句
The storms had abated by the time they rounded Cape Horn.
他们绕过合恩角时，暴风雨已经减弱。

also

adv. 也，同样，并且；conj. 另外；

例句
The media have also abetted the feeling of unreality.
媒体也在一旁对这种非现实感推波助澜。

seemed

v. 好像，仿佛( seem的过去式和过去分词 )；

例句
Steve seemed to acquiesce in the decision...
史蒂夫好像默认了这个决定。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

very

adj. 很，非常，恰好是，正是，十足的，特有的；adv. 很，非常，充分，完全；

例句
Most people have very little difficulty in seeing why a Van Gogh is a work of genius.
多数人不难理解为什么凡·高的作品是天才之作。

doubtful

adj. 难以预测的，难以预料的，未定局的，怀疑的，拿不准的，不明不白；

例句
For a time it seemed doubtful that he would move at all...
有一段时间他似乎根本不会搬家。

value

n. 价值，价格，意义，涵义，重要性，（邮票的）面

例句
Cheques can only be accepted up to the value guaranteed on the card...
支票的承兑金额不可高于卡上所担保的数额。