男性,34岁,体检时发现一度房宣传导阻滞,其他均正常,该患者查体可见
A.S1减弱
B.S1增强
C.S2通常分裂
D.收缩早期喷射音
E.S1分裂
参考答案:A
Some researchers believe that many patterns of nature are rules of their own and not affected by natural selection.
A.making
B.breaking
C.following
D.bending
图纸格式分为()和()种,按标题栏的方位又可将图纸格式分为x型和Y型两种。