问题补充：
Busy as Tom is, exercise has always been his work.
A. as a part of his life much as
B. as much a part of his life as
C. as much as a part of his life
D. so much a part of his life as
答案：
A. as a part of his life much as
(答案→)B. as much a part of his life as
C. as much as a part of his life
D. so much a part of his life as
解析：句意：尽管Tom很忙，锻炼一直像工作一样成为他生活的一部分。much用来修饰a part of his life,放在as…as中间。故选B。
