the winter in Harbin is rather cold, the city is still attractive to the visitors throughout the world.
A. Although B. But C. So
—______ did Samuel stand by the window so long?
—To see what would happen.
| A．How | B．When |
| C．What | D．Why |
—What else do you need for the trip, Mum?
—______ else. I think we have got everything ready.
| A．Nothing | B．Anything |
| C．Something | D．Everything |
Nanjing Underground Line 10 ______ on the morning of February 27th, 2014.
| A．tested | B．has tested |
| C．was tested | D．has been tested |
—Are you sure you have to? It’s been very late.
—I don’t know ______ if not now.
| A．where can I do it | B．why did I do it |
| C．when I can do it | D．how I will do it |
I ______ use a clock to wake me up because at six o’clock each morning the first train passes by my house.
| A．couldn’t | B．mustn’t |
| C．shouldn’t | D．needn’t |