问题补充：
At the beginning, I found it hard to get up early. Now I getting up early.
A. used to
B. am used to
C. use to
D. am used for
答案：
A. used to
(答案→)B. am used to
C. use to
D. am used for
解析：句意：在开始，我发现起床早很难。现在我习惯了早起。考查固定短语：be used to doing sth.习惯于做某事；used to do sth.过去常常做某事。故选B
