题目

 ____You should drive your car less. Otherwise, you’re likely tomore weight.             ____ You’re right. I need some walking exercise.          A. put up      B. put away         C. put out      D. put on 答案：D   “α,β,γ成等差数列”是“等式sin(α+γ)=sin2β成立”的A.必要但不充分条件                         B.充分而不必要条件C.充分必要条件                             D.既不充分也不必要条件