In many European countries, one has to decide much earlier what one’s career is going to be, and there is less freedom in changing one’s decision _____one has chosen a particular path[ ]

May I go out to play with my friends now, Dad—No. You ______ let your mother know first.

Unlike the earth, Mars is too cold and Venus is far too hot _______ there to be any life

Only at a stadium in Beijing ____________ many seats.

Did you take part in Mary’s birthday party last Friday?— I had ______ to, but one of my classmates called on me. [ ]