How is it structure ??

首先,第一句的意思是：將要跟他們會議的女人打了電話來告訴他們她不能出席會議。
換句話說， The woman they were meeting 的確是 subject
當然複雜啦。
至於that呢，是可以省略的，不過加了that確實是較清楚。如果你剛開始學這類句式，當然加that會比較容易明白，所以為安全起見都是加that比較穩陣。

在您補充的句子中，有三個錯處：


打錯woman這裡一定一定要加that，跟上面不同They were meeting 錯，應改成the meeting。改了以後的句子反而複雜了一點，因為它有另外一各意思：
那個女人打電話來告訴他們她不能在會議之前到達。
那是完全不同的意思呢！

最後，開頭兩個中文意思中，第一個意思應這樣寫：
After a teleconference, the woman said that she could not come.

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你的「除非」理解正確，
The woman they were meeting當中the woman係個subject，不過當中有一段subordinate clause "they were meeting"來表達（解釋）在全世界的女人中我在說那一個女人 - 那個他們假設要會見的女人(詳解用were meeting的意思)，當中冇寫一個whom(舊式英文)或who(一般)。

The woman, who they were meeting, has telephoned....
所以woman第三身單數，所以has...

they were meeting應該並不是過去進行式，而應該係假設或懷疑句，所以用了were，詳(長)句可能是they were supposed to be meeting。中間的很多「意會」的字都省卻了，英語人真是這樣講的。假如解作『「之前他們正在會見的那個女人」打電話來說她現在(present tense "cannot")不來見他們了。』是解不通的。
應該解作『「那個他們預備會見的」女人來電說她不來了。』

你觀察這句的結構很複雜是正確的，因此以後問問題請不要斬件"they were meeting點解"所給你的回應是幫助不了你的。坦白講用這句學subject-verb的example真係死得人多。

The woman whom they were meeting, has telephoned to say that she cannot come.

其實都不是太複雜，只要加翻兩個THAT就可以睇明啦。

The woman that/who they were meeting has telephoned to say that she can not come.



the sentence structure is the same as follows

The girl that/who I like thinks that she doesnt like me.

that/who 用來補充更多的資料而己，而後面的係常見的THAT CLAUSE.


省略 補充資料，句子可以寫成

The girl thinks that she doesnt like me.



明啦瓜

its not make sence
you should write like that
1.before the meeting Miss XXX ring up she can't come.
because woman is who not one know. therefore you have to show the name.
and you was too mass for logical thought.
or you can said Miss XXX had ring you won't attent for this meeting.

2010-01-13 14:12:59 補充：
telephoneed- in the real world we will say call, ring up or phone to. there are no such speak say telephone. and telephone is object not verb

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