Сделать ! choose the correct verb form. 1. how long has omar been studying\does he study\ at school #15? 2. my friend has been looking\looked\ for a bike for 3 weeks. 3. i whore\have been writing\ this exercise since 4 o'clock p.m. 4. i am tired because i wrote\have been writing\ this exercise since 4 o'clock p.m. 5. my friend is working\has been working\ as an air hostess since last month. 6. i have bought\bought\ a dictionary a few months ago.