作业帮long have you been in this city?—How long have you been in this city?—____C____ twenty years.A.Before B.After C.For D.Since求解析和翻译
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long have you been in this city?—How long have you been in this city?—____C____ twenty years.A.Before B.After C.For D.Since求解析和翻译
long have you been in this city?
—How long have you been in this city?
—____C____ twenty years.
A.Before B.After C.For D.Since
求解析和翻译
long have you been in this city?—How long have you been in this city?—____C____ twenty years.A.Before B.After C.For D.Since求解析和翻译
回答是I have been in this city for twenty years.
省略了I have been in this city .
在回答在某地已经呆了多长时间的时候,在时间前都要加for
选择C.
解释：回答可以还原为“I have been here for 20 years.”
A,B选项不能用于这种类型的问句回答。
D选项的since 应该直接接时间点，比如“i have been here since 2009.”这样就可以了。
C for+一段时间，强调时间持续的长度
A和B通常用来回答When引导的特殊疑问句，而且问句是现在完成时，带有before和after引导的时间状语的句子通常不用完成时。
例如：I came to the city before 1980.
如果要用since的话，正确用法是since twenty years ago
翻译 你在这个城市待了多久了？
A ：20年之前 错
B ：20年之后 错
C ：20年 for 加在时间前可以表示一段时间的长度 正确
D ：自从20年 错