how long have you been doing that为什么用现在完成进行时

how long have you be in here怎么回答 How long have you been how long were you in japan how long have you been in japan?how long will you be in janpan?分别 How long was it be,since i held you near?How long will it be,till i have you right here?小弟英语不好, how long have you been learning english? How long have you been studying? How long have you been in China? how long have you been dancing today? how long have you studied in this How long have you been there? How long have you live in China How long have you ----(live)here? “How long have you been watching How long will you be a___ how long have you been up?How long have you___up?A.got B.get C.been D.be这里为什么不选A? how long have you done与how long have you been的区别 How long have you been skating?与How long did you skate?的区别 How Long have you felt thisHow Long have you felt this way?翻译成汉语