问题补充：
people in the world are sending are receiving e-mails every day.
A. Million of
B. Many millions of
C. Several millions’
D. Several millions
答案：
A. Million of
(答案→)B. Many millions of
C. Several millions’
D. Several millions
解析：million前需用数表确切数量，而不用many这类词，但可说many millions of（上百万的）
