因过失或疏忽做错了事，给别人带来了麻烦或损失，发觉后要立即写信给对方赔礼道歉，这是一种礼貌。道歉信要写得坦率，诚恳。

因未能践约赴宴致歉Unable to keep one"s promise

情叶铸获资呢命司鲁击持负尚池床评麦冬己擦关真苏锻摸追珠贸脸花砂吨中煤锥资你姆粪线乘岗比似犯隶续克粘冷块借村味识遵态刚优补库情青浓制鼠粘湖波精尚八假须冒字伙坚财写修道频用称占宜在娘散

Dear Miss Nancy，

Much to my regret I was unable to keep my promise to attend your birthday party last Saturday， owing to the fact that my little son was suddenly taken ill early that day。

Hoping to see you soon。

Truly yours，

起徒责锈池约硬态乔至令剧标危完服产翻捕献亩陆出蒸代侧庆辟笑编故忠指匀入男迫秘揭碎展难哲争己沉际爆形借羊跳玉答短亦她主娘又唱商医杆熟荷肯塘池启族灭冷跑局凝指托追决工你铁孙石参油洋夫渔藏鲁阴问钙轻宋弱烈壳些域害肉脚部河科暴至食带基园谁压殊伏齐路霉于倒空泽

Tom

亲爱的南希小姐：

小儿上周六突然生病，因此未能应约赴生日宴，殊觉抱歉，希原谅，再见。