had 解不通== 請幫忙

The difference between the (1)were construction and the (2)had one is that the first generally has an active meaning, the second a passive one.Compare:-
eg:-(1)her hands and clothes were muddy.
eg:-(2)Katie had muddy hands and clothes;
(2)had
=an active meaning
=Her hands were muddy
---put something in a condition
=had her hands muddy
---to experience something
=She had a good time

(1)She found her hands
=passive
=It was found by her
=passive
---Hence were has a passive meaning.

這處(這問題)並不單單子句的意思上是否能否取代，你是要從全句(全文)前後的修辭(不單是句法/文法)來看。假如我把你提議的句寫出來:

When she had finished, her hands and clothes were muddy, but she felt very proud.

你有否發現全段中she/her所講的是誰呢。英語句子組織上跟中文有些分別是可以把主詞(主角)放在不同的位置(當然不同位置的句法就要不同的寫法)，而當作者要在三組的描述(finished, muddy hands and clothes, felt proud)的同時把主角的名詞寫進去，他就要選擇最能表達出他想讀者注意的位置和關係。

小學生程度的寫法便會是：
When Katie had finished, she had muddy hands and clothes, but she felt very proud. 三句的結構文法都一樣。[S + V + O]

中學生程度可能識寫為：
When Katie had finished, her hands and clothes were muddy, but she felt very proud.
把中間一節的內容改為被動式形容，加強描寫時的觀感，而不單單旁述。

大學程度可能要從內容的表達重點著手，要引導讀者把主題或主旨看出來：
When she had finished, Katie had muddy hands and clothes, but she felt very proud.
把主角的名稱由句首改為寫在形容她狀態/情景的子句，突出當時"她"的情況讓讀者感受一身泥跟下一句她"很自豪"感受的對比。留意句子的寫法重點是Katie had和she felt這兩句文法/修辭結構的類似關係，就像寫"他有錢,但不(沒有)快樂"的寫法。但是假如改為合文法的寫法Katie's hand and clothes were muddy.便變為敘述而不是描寫，就像"他是個有錢人,但他不快樂"，雖然同樣加了一個"但"字，不過感覺上不能生產生那種對比感"有/沒有"/"辛苦/自豪"。

由於這是修辭寫法和作者期望的表達，以上解答只是講出原文的作用和你提問改寫的效果的分別。文法/句子結構上基本沒有錯的，甚至意義/意思上也看來一樣，但結合前後子句/文意就有不同的。

可以，原句的這個 "had" (本句是 have 的 past participle, 以 past tense 形式出現) 在英文上是一個特別用法，並不是直譯為「有」。

例如：
I have my house painted. 意思上= My house was painted.

I asked somebody to paint my house and he did and it means that My house was painted by someone

had / got something done (by someone)

2014-08-19 14:54:46 補充：
又例如：I have my homework done!

在這些句子中，have 都不是譯作「有」。

2014-08-19 14:55:42 補充：
When she had finished, Katie had muddy hands and clothes, but she felt very proud.

當她完成了，她雙手和衣服沾滿污泥，但她感到很自豪。