two and a half month(s),month后加不加swhy

two and a half month(s),month后加不加s? two and a half month(s),month后加不加swhy He has been there for__A two and a half month B two and a half months C two and the half months D two and half a month he has been in Shanghai for ( )A.two and a half months B.two and half a month C.two month and a half D.two months and half It took me _______to finish the project.A.a half and two months B.two month and a halfC.two and a half month D.two and a half months He has been here for __.A.two and a half monthsB.two and half a monthC.two and half monthsD.two and a half month为什么选A呢? We have been here for_____.A two and a half months B two and half a month C two and a half month选哪个?为什么?为什么其他不行? He has been there for__ A.two and a haif hours B.two and a half months c.two and haif a month 1：Miss Gao will stay in Nanning for about ______( )A:three months and a half B:three month and a half C:three and a half month D:three months and half2：He's been a soldier for nearly ______( )A:half and two years B:two and half yearC:two years an How long will you stay here A.two and a half month B.two and a half months C.two months and half请附带A、B、C三个选项的注解, month and a halfThe Antarctica explorers stayed on that ice-covered continent for____.A.a month and a half B.one and a half month c.a half and a month d.a half and one month 说明下理由 one month and a half和one and a half month有区别吗?还有one hour and a half和one and half an hour哪个对? Two And A Half Men中文翻译 - years ago ,I came to the USA.Two and a half Two and half a Two a half Half and two The huge elephent weights____.A two tons and a half B.two and a half ton C.half and two tonDtwo ton and a half one and a half month还是months对? one and a half month用加s吗? one and a half month one and a half months 那个正确呀,为什么呀