He told me that he had had a cold for three days.
主句是过去式,从句的完成时是过去完成时had+done
由于得了感冒是have a cold,have的过分分词是had
那么就是 had had a cold
这个句子的意思：他告诉我他得感冒已经三天了.very very very感谢！我后天考试，复习时正搞不懂呢！多亏有你帮我，解了我燃眉之急！非常感谢！逻辑很清晰！