作业帮请问since与for怎么使用,怎么样来理解啊?
来源：学生作业帮 编辑：作业帮 分类：英语作业 时间：2024/05/24 17:24:21
请问since与for怎么使用,怎么样来理解啊?
last month, 是个时间点,since last month
从last month 到现在就是一个时间段,要用 for a month.
所以这句也可以说：I have not smoked for a month = since I quit smoking last month/ a month ago.
since + 时间起点/ 过去动词的时间状语从句：从……起,到说话时：自从……以来
for + 时间段：长达/连续……时间
两者作用是一样的：
我5年前来北京工作的.= 从5前到现在我在北京工作.=我在北京已工作5个年头了.
I began to work in Beijing 5 years ago and now I am working here.
= I have worked in Beijing since 5 years ago.
= I have worked in Beijing since I came 5 years ago.
= I have worked in Beijing for 5 years. ( from 2006 to 2011= for 5 years)
从last month 到现在就是一个时间段,要用 for a month.
所以这句也可以说：I have not smoked for a month = since I quit smoking last month/ a month ago.
since + 时间起点/ 过去动词的时间状语从句：从……起,到说话时：自从……以来
for + 时间段：长达/连续……时间
两者作用是一样的：
我5年前来北京工作的.= 从5前到现在我在北京工作.=我在北京已工作5个年头了.
I began to work in Beijing 5 years ago and now I am working here.
= I have worked in Beijing since 5 years ago.
= I have worked in Beijing since I came 5 years ago.
= I have worked in Beijing for 5 years. ( from 2006 to 2011= for 5 years)