—How well do you know the Opera House?—I know the place very well. I ____ Sydney many times.
______ Lily ______ Lucy may go with you because one of them must stay at home.
—Have you ever heard of Langlang?—Sure. He is one of ______ pianists ______ I have even seen.
—Have you heard of the Big Ben? —Of course. It a symbol of UK.
—Please say something about Zheng He.—Oh! He is the Ming dynasty explorer of ______ all the Chinese are proud.
—Where is North Korea?—It lies ______ the northeast of China.