The Klondike was the_____ of one of the biggest gold rushes the world has ever known.
– The lecture will begin at 4 o’clock in the afternoon, right? – Yeah, ____ you get there on time.
– Tom has made great progress in spelling. – So he has and _____.
The mayor will go to Beijing by train _____ by air.
Living in a big city has many _____, such as good schools, libraries and convenient traffic.
Father _____ goes to the gym with us although he dislikes going there.