__Dad ,how can I get on well with my xlassmates?

—Tryto be friendly to them .That will make it much____.

A．easily

B．more easily

C．easy

D．easier

二尖瓣狭窄患者，提示其瓣膜尚有一定弹性的听诊标志是______

A．心尖区第一心音减弱
B．舒张期杂音局限不传导
C．肺动脉瓣区第二心音分裂
D．二尖瓣开放拍击音
E．吸气时杂音减轻或消失