He's been here for 10 years, _____?[ ]
A. is he
B. hasn't he
C. has he
D. isn't he
答案:B
发生交通事故,经公安机关交通管理部门调解,当事人未达成协议或者调解书生效后不履行的,当事人可以向()提起民事诉讼。
A.公安机关
B.人民法院
C.人民政府
D.交警大队
动物怎样调节热平衡?