I'm in New York with my parents and my sisters since one week.
The sentence is from a letter written by a teacher. Is "since one week" grammatical?
I'm not sure that in the sentence, the use of tense and adverbial is correct.
I'm in New York with my parents and my sisters since one week.
The sentence is from a letter written by a teacher. Is "since one week" grammatical?
I'm not sure that in the sentence, the use of tense and adverbial is correct.
It depends. If you mean a one week period of time, and you are still there, then:
I have been in New York with my parents and my sisters for one week.
If you mean the 7 days prior to the statement, then:
I have been in New York with my parents and my sisters since one week ago.
I prefer have been since you are referring to a period of time.