The retired professor, _____ in his new book in the past three years, hasn’t realized the decline in his health.
I _____ through the hard time but for my teacher’s generous and timely help.
The class teacher was anxious to hear one of his top students _____ because of family move.
With the exam ______ in ten minutes, they were asked to hand in their mobile phones.
More than one doctor _____ involved in the rescue that took place after the earthquake.
Some hard-working students always keep a torch in their dormitories _____ there is a power failure.