问题补充:
It is difficult for any of us to eat better, exercise more and sleep enough we know we should.
A. despite
B. even though
C. as if
D. unless
答案:
A. despite
(答案→)B. even though
C. as if
D. unless
解析:考查词性词义:A. despite介词,虽然,B. even though连词,既然,C. as if 连词,好像,D. unless连词;除非,句意是:我们每个人想吃得好,多锻炼,睡眠足够都很难,即使我们知道应该这么做。选B。A的词性不对。