题干
Class is over. The students stop and start .
A：writing; to talk
B：to write; talk
C：writing; talk
D：to write; talking
答案(点此获取答案解析）
A
Class is over. The students stop and start .
A：writing; to talk
B：to write; talk
C：writing; talk
D：to write; talking
的内角
的对边分别为
，若
，