John opened the door. There _______ he had never seen before.
What especially impressed us was the way_____the girl studied foreign languages.
The young boy got himself into a dangerous situation_____he might lose control over his sports car.
What if we meet with a situation_____none of us are able to deal with?
_____has happened many times, children may get drowned in this river.
There is a mountain_____the top is always covered with snow.