【題目】The plane is fast, but it's expensive. I ________ take a train to get there.
【題目】________ you attend the meeting? I'm really looking forward to seeing you.
【題目】It's my turn to be on duty today. You ________ clean the classroom.
【題目】I'm afraid you ________ smoke here. Look at the sign "No smoking!".
【題目】The society is developing fast. We________ keep learning to catch up with the development.
【題目】That boy ________ be Tom. He has gone to his hometown to visit his grandparents.
【題目】Students ________ read more books because they can help them be better people.
【題目】Have a glass of water, please. You ________ be thirsty after a long walk.
【題目】Necessary action ________ be taken to protect the environment so that we can have a better world.