题干
一 Be careful, ________ you will make mistakes in your exams.
— I know that, Mum. One can never be too careful.
A：and
B：or
C：nor
D：but
答案(点此获取答案解析）
B
一 Be careful, ________ you will make mistakes in your exams.
— I know that, Mum. One can never be too careful.
A：and
B：or
C：nor
D：but
的终边过点
，且
，则
的值为（ ）