Form general or special questions with the question word given. 1. We have been friends since childhood, (since when)

1. We have been friends since childhood. (Since when have we been friends?) 2. The rain hasn\'t stopped yet. (Has the rain stopped already?) 3. The film has been on for a week. (How long has the film been on?) 4. He had recovered by the time I returned from my leave. (Had he recovered by the time I returned from my leave?) 5. He will have worked as a teacher for 20 years by next September. (How long will he have worked as a teacher by next September?) 6. The students will have started the discussion by the time you come. (Who will have started the discussion by the you come?)