Question

"If you really want yourself to be in good health, you must＿＿＿always＿＿＿so m"

"If you really want yourself to be in good health, you must＿＿＿always＿＿＿so much.
A. not； be smoking
B. not； have smoked
C. not； to smoke
D. be not； smoking"

Answer 1

答案A
mustn’t be doing与always连用，表示“一定不要总是在做……”，含有“埋怨、不满”等感情色彩。
参考：http://www.zuoyebao.com/q/19623