缩窄性心包炎最常见的体征是
A.气促
B.肺部罗音
C.心浊音界增大
D.颈静脉怒张、肝大、腹水
E.奇脉
参考答案:D
You should apologize ____ your teacher ______ being late again.
A.to; for
B.for; to
C./; for
D.to; to
简述覆盖除草的原理及其除草方式?