--This kind of sports is exciting.--Yes,but it's dangerous.One can't do it ____ he or she has got some training.
There’s water all over the kitchen. You’d better _______ right away.
I saw a number of pancakes in the plate, but now there is _______ left in it.
— Would you like to attend China’s Got Talent《中国达人秀》? — _______, but I’m busy preparing for my test.
What action should they _______ such a thing happening again?
_______ you are busy now, let’s go next time, OK?