since when ,how long 区别
是不是when.现在完成时.since.how long 现在完成时 .for.
when和how long的区别是什么?
when\how long\how ofter有什么区别
请区别when,how long 和how soon
how long、how much longer、how late、when、how far、how soon解释、区别
when 和how long提问时间,有什么区别
long before和long since 区别
How long have you__?-Since 1990.
when did you moved here和how long have you lived here有区别吗
Ian has lived here since 1976对since 1976提问为什么用how long how l
how soon和how long 区别!
how far 和how long 的区别?