had not ,did not have運用不明白

前面係past tense 後面都係past tense

如果後面用had not, 會變左 but she had not had a fever (過去完成式)
文法上唔make sense 個意思亦會變左

she did not have a fever = 冇發燒
she had not had a fever = 仲未發燒

have 有兩種不同的用法，一種是動詞，解"有"，另一種是助動詞，沒有意思。
動詞時，She had a cold，她有感冒，She had not a cold沒有意思的，也不完整，只有She had not had a cold用過去完成式時才有意思。同樣道理也應用在do上，do可以是動詞，解"做"，也可是助動詞，沒有意思。She had a cold中的had並不是助動詞，而是解"有"，所以要加not時應補上do，過去式轉為did，然後再加not。

2011-03-27 23:20:36 補充：
又如：I have done a great job. (have是助動詞)
I have not done a great job.
又如：I have a job. (have是動詞，解"有")
I don't have a job.