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(单选题)Many Americans fail to lose weight probably because ______. (单选题)（ ） (单选题)You cannot go outside since it is too late; _____ it is rain (单选题)It will be many years ______ the doctors and medical scienti (单选题)______ to the polluted air is dangerous for our health. (单选题)At present, there are many instances ______ the governments (单选题)The auto-company succeeded in developing a new type of new e (单选题)—What do you think of her suggestion?—______, it would be mu (单选题)My brother left home five years ago. I ______ nothing from h (单选题)He regretted ______ a second-hand car.