According to the law of traffic safety, drivers ______ back their cars at the railway crossing, intersection, sharp bend, steep slope and the tunnel.

(单选题)______ to think critically is an important skill today’s chi (单选题)—I am very proud of the ______ China has made to fighting ag (单选题)—I hate school; it is not for me. I think I’ll quit.—You ___ (单选题)My friend Lucy is always complaining about her job as a teac (单选题)I had always considered acupuncture（针灸）old-fashioned. But th (单选题)The stress of the following words are all on the first sylla (单选题)Which of the following would be the best title for the text? (单选题)One problem with the PreCheck program is . (单选题)Which of the following contributes to long waits at major ai (单选题)The crash of Egypt Air Flight 804 is mentioned to .