是in 1980s对还是in the 1980s对?

是in 1980s对还是in the 1980s对? 是in1980s还是in the 1980s 是in the barber's 还是at barber's 是in the 1980's还是in 1980's好像1980's和1980s是一样的?1980s和1980's是一样哒 兄弟们 in the 1970s；in 1970s；in 1970's；in the 1970's哪个对? I have served army___when I was__. A.in the 1980's,in the twenties B.in the 1980's,in my twenties在某人20岁, 到底是in the twenties还是 in my twenties?谢谢各位! 在90年代是 in 90s 还是in the 90s?那么,in the 1620s 是什么意思? in the 1990s'还是in the 1990's “在二十世纪八十年代”,用英语怎么说?是“in the 1980s”还是“in 1980s”? in the 1950s 还是in 1950sin the 1950's 还是 in 1950's in the 1980s和in the 1980's是不是都对的?有差别马? 在20世纪60年代 英语是in 1960s还是in the 1960s 在80年代,英语表达法是in 80s 还是 in the 80s 是It's in north of China.还是It's in the north of China in 1950s 与in the 1950s有什么区别?in 1950s是表示1950----1959还是1940---1949?in the 1950s呢? There is ) s in the small是 a 还是 an Shakespeare was born in the 1560's/in the 1560s/in 1560s/in 1560's哪个是对的 in 1990s还是in the 1990s