题干
— I know your name?
— Linda.
A：May
B：Do
C：Need
D：Am
答案(点此获取答案解析）
A
— I know your name?
— Linda.
A：May
B：Do
C：Need
D：Am
,
(如右上图);当甲,乙行走的速度相同(不为零)时刻: