From the first paragraph, we know that ______.

(单选题)He put up a sign ______ “Keep off the grass”. (单选题)—My room gets very cold at night.— ______. (单选题)—Could you please tell me ______?—With pleasure. Wait a mome (单选题)—Hey, do you know who the guy is over there?—Oh, yes. He ___ (单选题)How many ______ are there in your school? (单选题)Would you like ______ tea ______ milk? (单选题)What attitude did Haldane have towards the future employment (单选题)What should be done to deal with the serious situation? (单选题)Why are economists the lucky dog in the new technological re (单选题)What is the dark side mentioned in the text?