Who knows but that he will come soon ? 谁知道他会马上来 ?
Who knows but that it may be so ? 可能如此，谁知道 ?
5 . “not so … but…”，“ not such a + n … but …”—没有……以致于不……(尽管……仍……)。but = that not ，具有否定意义，引出一个相当于否定的结果语从句。例如：
He is not so sick but he can come to school . (= that he cannot come …)
他并没有病重到不能上学的程度。
He is not such a fool but he can tell a friend from a foe . 他不至于蠢到敌友不分的地步。
No man is so old but he may learn . 没有老到不能学习的人(活到老，学到老。)
6 . \"not … but …”，“never … but …”和“hardly / scarcely … but … ”—没有……不……。but 具有否定意义，but 实质上引出一个带有否定意义的定语从句。例如：
There is no rule but has exceptions . ( = which does not have … )
没有一个无例外的规则。(凡规则都有例外。)
No tourist but wants to go to see the Great Wall . (= who does not want …)
没有一个旅游者不想看看长城的。
Scarcely a week passes but she writes to her parents . ( = when she does not writes to …)
几乎没有一个星期她没写信给她的父母亲的。(她差不多每个星期都给她的父母亲写信。)
7 . who / what … but … —除……之外，没有 …… 。例如：
Who but a fool would do such a thing ? 除了傻子之外，谁会做这样的事 ?
Whose fault is it but hers ? 这就是她的错。(除了她错之外，没有人错。)
What is coal but a kind of stone ? 煤只是一种石头。
8 . who / what … should but … —“除了……还会有……呢?”“想不到(岂料)竟是……”，或“……正好是……”。表示意料之外的事情。例如：
Who should fail but that man ? 除那人之外，还会有谁失败呢 ?
The door opened , and who should enter but the very man we were talking of ?
门开了，岂料进来的正是我们刚才谈论的那个人。
What should I find but an enormous spider ? 岂料，我看到的竟是一只巨大的蜘蛛。
9 . but what ，具有否定意义，在名词后起关系词作用，引出定语从句；在及物动词后，引出宾语从句，表示“未必不”或“也未可知”。例如：
There are no events but what have meaning . ( = which do not have … )
但凡发生的事件都必有其意义。(没有发生的事件没有意义)。
Not a day passes but what it rains . (when it does not rain . ) 没有一天不下雨的。
I don\'t know but what I will go . ( = that not ) 我不知道我是不是去。(我或者去也未可知)。
Who knows but what it may be so ? 谁知道也许不是如此。
【动脑动手】
“喜迎澳门回归祖国，热烈拥抱2000元旦”中视图文特别奉献
1 . Every hour on the CCTV ____ the latest news in Iraq .
A . announced B . reported C . is broadcasted D . published
2 . Alice ____ me to phone her father and she did so .
A . permitted B . advised C . promised D . persuaded
3 . Unless the worker\'s demands are ____ soon there will be a strike .
A . permitted B . paid C . met D . replied
4 . — You may need help .
— If I do I\'ll ____ you to help me .
A . turn to B . depend on C . ask for D . look for
5 . — Where does your English teacher come from ?
— I\'m not sure , but his Chinese ____ Shanghai .
A . suggests B . sounds C . listens D . hears
6 . ____ not knowing the answer to such an easy question!