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(单选题)According to journal of adolescent health’s study, ______. (单选题)What can be inferred about instant messaging applications? (单选题)What’s the main idea of the text? (单选题)（ ） (单选题)I need the money badly now and I have to ______ my car thoug (单选题)We are going to have the sports meeting ______ it ______ tom (单选题)—Have you completed your paper?—Not yet. I ______ the last c (单选题)China is seeking ______ access to ______ more friendly envir (单选题)We were all excited at the news ______ our annual sales had (单选题)After the Shenzhou VI capsule (太空舱) touched down, two astron