______can you stay there? --For two weeks.A. How longB. How farC. How often
—Is Mr Hu driving here? —I’m not sure. He ___________ come by train.
—Who is singing in the next room? —___________ must be Marie.
—TV says there will be a storm tomorrow. —___________, I planned to go climbing with my classmates.
Smile to the world, ___________ the world will smile back to you.
—What do you often pay attention to when you learn English? —___________.