英语问题HarryleftthistowninJanuaryandwehaven'tseenhim()?Howlongisit()youwrotetoyoursister?Howlong()didyouwritetoyoursister?用since,for,ago填空,顺便问问since的用法,和时态问题,急需,明天要交作业

Question

英语问题
Harry left this town in January and we haven't seen him( )?
How long is it ( )you wrote to your sister?
How long ( )did you write to your sister?
用since,for,ago填空,顺便问问since的用法,和时态问题,急需,明天要交作业

Answer 1

since
for
ago
先大致说说since的用法
1 作prep讲时,与现在完成时态或过去完成时态连用,表示从过去某时间以来、以后或到现在.
如：I haven';t eaten since breakfast.
2 作conj讲时,与主句中的现在完成时态、过去完成时态或一般现在时态连用,表示从过去某事以来、以后或者现在.
如：How long is it since we visited your mother?
3 作adv讲时,与现在完成时态或过去完成时态连用,表示从过去某时间以来、以后或到现在.
如：He left home two weeks ago and we haven';t heard from him since.
4It is + 时间段 + since 从句,since 从句要用过去时.
It was + 时间段 + since 从句,since 从句要用过去完成时.