have been studying过去进行?用法?
have been studying过去进行?用法?
英语have been studying过去进行?用法?
have 动词过去分词.和have been 过去分词的用法
How long have you been studying English?
i have been studying history in china
How long have you been studying?
have been 的用法
have been的用法
have been 用法
have been 的用法?
现在完成进行时的被动语态结构是have been +过去分词还是have been+doing
完成进行时(have+been+现在分词) 完成时被动语态(have+been+过去分词) 现在完成时(have+过去分