London is a big city, _____ 7 million people.[ ]

Listen! Is Mary playing the piano in the room? –No. It ________ be Mary. She has gone to Hong Kong.

Math is difficult for me. How I wish to improve it!－Don’t lose your confidence. I believe you will ______ it if you keep trying.

Is that Jack speaking?—Sorry, he isn’t here. He ________the cinema with his aunt.

You _________ drive so fast, for we have enough time to arrive at the station.