绿草泱泱
现在分词做状语，letter ，inform 信告诉我 是主动关系 所以要用现在分词表主动。至于为什么要用逗号，你可以把他当那当做是分词做状语的标志句子主语 I 谓语 have received 宾语 a letter informing 后面整个都是状语，这个状语中又有一个that 宾语从句，宾语从句的主语是 my former headmster ， Mr.Stuart Page是插入语， will be retiring 是宾语从句的谓语
浮生若梦762
The headmaster's speech was not long. He said he thanked pupils for their coming and joining this farewell party and presenting him so much good presents. He remembered pupils past and present and those days they ever went pass together. Many of them had got the successful careers and some of them had become the important leaders and managers in many big companies. But he hadn't forgotten those humorous incidents which had happened among them in the past time.At the last he spoke of his own future. He said he had happy memories of his served school, Old pupils would be welcome to come and visit him in the future. He told us how he would spend his time. Gardening was his best selection. It would take him forty years to put his garden in order
xiaoyimoon
这里不是定语，而是分词作状语分析句子成分的话，I have received a letter from my old school我想就不必分析了。从informing开始到最后都是状语，从that开始到最后都是宾语从句
大鹏村长
lesson48didyouwanttotellmesomethingthedentistinthestoryhadpulledoutoneofthewriter’steethandhadtoldhimtorestforawhile.heaskedseveralquestionsbutthewritercouldn’tanswerthem.hismouthwasfullofcottonwool.hesuddenlydiscoveredsomethingwrongbuthecouldn’tsayanything.thedentisteventuallyremovedthecottonwoolfromhismouthandthewritertoldhimhehadpulledoutthewrongtooth.(72words)
