Question

在现在完成时中for,since的区别.

请造一个例句。谢谢。

Answer 1

since可以放在句首，而for不可以。另外，since是点时间，相当于when的意义；for是段时间，相当于while的意义！
It has been a long time since we last saw each other.
We haven't saw each other for quite a long time.

Answer 2

现在完成时中since和for的区分

Answer 3

We've got some food to eat for tomorrow already.
我们已经有明天吃的食物了。
Since we've got plenty food in the fridge, you don't have to worry about us for tomorrow.
你不用替我们担心明天，因为我们有很多食物在冰箱里。

Answer 4

since
+
[过去的]年分
/
月分
/
季节
since
2014
;
since
last
month;
since
february
/
since
this
spring
/
since
last
summer
/
since
the
80's
for
+ 时间/
年
/
月
/
日
for
three
hours
;
for
five
years
;
for
two
months
;
for
four
days
;
for
many
years

Answer 5

for加时间段
since加时间点
I've been a student for 10 years/since 10 years ago