Nowadays there are still a number of students school at various grades due to a lack of money in some poorer areas.
---Could you tell me ___ all of you think of your teacher? ---She’s a good teacher.
All ___ can be done has been done.
The train __ for five minutes by the time we got there.
It ___ to be raining when we went to see him off at a railway station.
---I left my pen at home. ---___! Use mine.