Present perfect and present perfect progressive put in the correct form: 1) how long have you sasha? (know) 2) how long have you english? (study) 3) each other since 1993. (know) 4) joey and sasha friends for several weeks. (be)

1 How long have you known Sasha?
2 How long have you been studying English?
3 We have known each other since 1993.
4 Joey and Sasha have been friends for several weeks.