题干
People in the west make_______a rule to buy Christmas presents for their friends.
A： that
B：it
C： thi
D： a
答案(点此获取答案解析）
B
A： that
B：it
C： thi
D： a
=
tan
-
sin
+4(其中
0),如果
,则
(2010
-3)的值为 ( )