in+时间往往用于一般将来时中,如:I'll go back home in three days.三天后我回家。 after+时间,表示比...时间更晚 ,可用于各种时态中。如: They have left after lunch他们午饭后离开。 Shortly after six,the telephone rang.刚过六点钟,电话铃响了。They said they would finish it the day after tomorrow.他们说,后天他们将完工。 有用请采纳,谢谢!