all were Uighurs

enti

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" Z2 \0 \4 G4 R8 PCAIRO — At least 12 Chinese nationals were deported and put on a flight to China late Thursday, and 22 more were detained for immediate deportation, three Egyptian aviation officials said.
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According to a Chinese student who said he was friends with some of those detained, all were Uighurs, members of an ethnic group that is mostly Sunni Muslim and lives mainly in the western Chinese region of Xinjiang. The student, Muhammed Emin Nurmuhammed, said that his friends had been studying at Al Azhar, a mosque and university in Cairo.

我的问题是怎么知道它不是个非限定性的定语从句呢? 毕竟 members of an ethnic group... 就是它的定语从句了。 同样的也是这种形式，怎么区分呢？ 为什么它就不可以是 “some of those detained“的定语从句呢？
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fellboy

1. all were Uighurs 是一个主系表句子，而非定语从句。定语从句要有关系代词（who, which, that, ...）或是关系副词（when, where, why）来引导；
2. all were Uighurs, members of an ethnic group that is mostly Sunni Muslim and lives mainly in the western Chinese region of Xinjiang. 后面的 members of an ethnic group... 这儿是一个同位语。... that is... 是引导一个定语从句，修饰先行词 an ethnic group。当然，你如果改成 members of which are ... and live .... 这样从语法上说得通，但句子重点有所偏倚。

trivialstuff

看不大懂你的提问，若说标红的“all were Uighurs”是定语从句，即理解成all of whom were Uighurs的话，那这整句话就全是从句没有主句了。
all were Uighurs是主句（all指代第一段的对象），members of an ethnic group是Uighurs的同位语，同位语中又有修饰ethnic group的限定性定语从句。试着把第二段前面的according to移到最后，理解上应该会少一点困惑。
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All (of those deported or detained) were Uighurs (= members of an ethnic group that is mostly Sunni Muslim and lives mainly in the western Chinese region of Xinjiang), according to a Chinese student who said he was friends with some of those detained.

jonah_w

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" n) k: c2 E& B5 C/ E" ?/ ~语法知识可以参考其他人的；另外提供一种思路：

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http://www.yinwang.org/blog-cn/2018/11/23/grammar
" E2 o2 w0 P, {0 F: r. n更新：适合早就学会并很熟悉语法基础的中高级英语学习者参考尝试。
学语法有两个极端，完全不学语法和过于看重语法，最好都不要…

enti

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" X( x. H9 h& [1 |+ C3 A8 v哦， 是了。 我光是记得有逗号就是非限定性定语从句， 感谢解惑。
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我收回这个问题, 没有主句哪来的从句, 我也是神经了.
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