问题补充：
.—What the twins on weekends?
—She usually goes skateboarding.
A. do, do
B. does, do
C. does, does
D. do, does
答案：
A. do, do
B. does, do
(答案→)C. does, does
D. do, does
解析：句意：——那对双保胎在周末干什么？——她经常去滑板。主语是the twins，故用助动词do来表示。疑问句的结构：疑问词+助动词+主语+动词原形，故选C。
