Believing that everyone can make _____ world _____ better place on a daily basis, Tom plays his part in helping others.

A．/, a

B．the, /

C．the, a

D．the, the

创伤性心包出血()

A．X线胸片呈肺野磨玻璃样变或面纱征

B．X线胸片呈多发边缘锐利、密度均匀高密度影

C．X线胸片呈一侧胸腔一片致密均匀阴影，纵隔向健侧移位

D．X线胸片呈纵隔气肿，大量气胸

E．X线胸片呈心影明显增大，心脏各弧消失