有這樣一道題，是考查except用法的：

A：Does he often come to see you?

B：No，the never comes ________ he is in trouble.

A. except B. except that C. except when D. except for

此題很容易誤選B，因為后面是一個從句，所以很容易聯想到except that，其實此題應選C。B，C 兩者之后均接從句，其區別主要從句意上看：except when中的when有“當……時”之意，而except that則無此義。比較：

I know nothing about him except that he lives in Paris. 我除知道他住在巴黎外，其他情況一無所知。

I like her except when she’s angry. 除了她發怒的時候，我還是挺喜歡她的。

except作為介詞，后接名詞或代詞(這是基本用法)，除了以上提到的后接that從句和when從句外，以下用法也需注意：

(1) 副詞：She has never come late except recently. 除了最近一段時間，她從未遲到。

(2) 介詞短語：The window is never opened except in summer. 除了在夏天外，這扇窗戶從不打開。

(3) 不定式(注意是否帶 to)：It had no effect except to make him angry. 除了惹他生氣外，沒產生任何效果。

There was little we could do except wait. 除了等待我們沒有什么辦法。

(4) what從句：I know nothing about it except what he told me. 除他告訴我的情況外，我對此事一無所知。

(5) where從句：My papers seem to be everywhere except where they ought to be. 我的文件似乎完全不在它們應該放置的地方。