In youth,we learn; In old age,we understand什么 意思

In youth,we learn; In old age,we understand什么 意思 In youth we learn; in age we understand里面in age这样用有问题么?还是用in old age?貌似是来自Marie von Ebner in my youth I am afraid who,my youth I make decision. I learn English in China in doing we learn嘛意思? Even in we must learn to smile, We must learn knowledge in m______ society. we spent our youth together,I don't own you,you don't owe me,Youth is used to misswe spent our youth together,I don't own you,you don't owe me,Youth is used to miss in youth 什么意思? i like all my lesson ,because we can learn a lot in them.此句中的in能否换成form Youth will lose, in the absence of the youth day, I hope to find the youth, also hope that the you帮忙翻译一下. 翻译：should the youth head in vians to turn grey ,we would regret the time. we--- each other in English a.learn b.learn to c.are learning d.learn from We have spent nine years___Chinese.A,on learn B in learning C to learn D learn Each of us decided (work)in the west after we left school I found it hard (learn) English well. Where can I learn Chinese in Shanghai? Where can I learn Chinese in changchun? I read your advertisement in china youth Daily yI read your advertisement in china youth Daily yesterday about hiringa teacher teaching chinese .about、、、、是做什么成份啊?