We planned to climb the mountain today, but in such ________ bad weather, it seems out of ________ question.
The teacher is not only strict ____ his pupils but also strict ____ his own work.
Mary dropped in ____ Mr Smith, but he wasn' t at home, so she went to drop in ____ Mr Smith's office.
The worker can make chairs ____ wood, and also can make paper ____ wood.
The teacher is writing ____ a piece of chalk on the blackboard while the students are writing ____ink in exercise books.
There are altogether eleven books on the shelf, ______five are mine.