—Oh, I forgot to tell you. Many children ____ (celebrate) Ann's birthday.

-- Excuse me. Where _______ Andy ________ from?

-- Nanjing.  

黄河中下游含沙量大的重要原因是（    ）

—I am really struck by your spoken English. You speak so fluently. Have you been abroad?

—Yes. I ______ in London for two years.