适用于一切确已成脓者的是（）
A.砭镰法
B.切开法
C.挑治法
D.挂线法
E.结扎法
参考答案：B
It was impolite of him ____without ____good－bye
A．to leave; saying
B． leaving; to say
C． to leave; to say
D．leaving; saying
