有6题有关for及since用法,帮我看一下好吗?

有6题有关for及since用法,帮我看一下好吗?
1.She has studies English 【for】three years .
2.He has been at the hotel 【since】yesterday .
3.She has lived in Brazil 【for】a long time .
4.He has taught Italian 【since】last September .
5.He has had a cold 【for】four days .
6.They have been friends 【since】six years.
这是我自己写的,不确定是否正确 = =
可不可以加一个翻译,顺便告诉我 我写的对不对呢?!
呵呵,不好意思,我英文很烂 ...